def buildPairFeatures(ff, pair_type, classification, et_opt, ee_opt):
    event_event_str = ""
    event_timex_str = ""
    timex_timex_str = ""

    event_timex_dct = ""
    event_timex_non_dct = ""
    event_timex_main = ""
    event_event_main = ""

    n_ee_pairs = 0
    n_et_pairs = 0
    n_tt_pairs = 0

    for (e1, e2) in ff.tlink:
        #print e1, e2, ff.tlink[(e1, e2)]
        if e1 in ff.entities and e2 in ff.entities:
            if ff.isTimex(e1):
                (eidx1, tid_start1, tid_end1, timex_type1, timex_value1,
                 dct1) = ff.entities[e1]
                if dct1: sentid1 = "O"
                else:
                    (_, sentid1, _, _, _, _, _, _, _, _, _, _,
                     _) = ff.tokens[tid_start1]
                (lemma1, token1) = ff.getLemmaTokenTimex(e1)

                if ff.isTimex(e2):  #timex-timex pair
                    #(eidx2, tid_start2, tid_end2, timex_type2, timex_value2, dct2) = ff.entities[e2]
                    #if dct2: sentid2 = "O"
                    #else: (_, sentid2, _, _, _, _, _, _, _, _, _, _, _) = ff.tokens[tid_start2]
                    #(lemma2, token2) = ff.getLemmaTokenTimex(e2)
                    #(sent_distance, ent_distance, ent_order) = ff.getDistance(sentid1, sentid2, eidx1, eidx2)
                    #(temp_conn1, temp_conn_pos1) = ff.getTemporalConnective(e1)
                    #(temp_conn2, temp_conn_pos2) = ff.getTemporalConnective(e2)
                    #(temp_signal1, temp_signal_pos1) = ff.getTemporalSignal(e1)
                    #(temp_signal2, temp_signal_pos2) = ff.getTemporalSignal(e2)

                    #tt_str = "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" % \
                    #    (e1, e2, token1, token2, sent_distance, ent_distance, ent_order, timex_type1+"-"+timex_type2, timex_value1+"-"+timex_value2, dct1, dct2, temp_signal1, temp_signal_pos1, temp_signal2, temp_signal_pos2, temp_conn1, temp_conn_pos1, temp_conn2, temp_conn_pos2)
                    #if classification == "bin":
                    #    if ff.tlink[(e1, e2)] != "NONE": rel_type = "REL"
                    #    else: rel_type = ff.tlink[(e1, e2)]
                    #    timex_timex_str += tt_str + "\t%s\n" % rel_type
                    #elif classification == "rel":
                    #    if ff.tlink[(e1, e2)] != "NONE": timex_timex_str += tt_str + "\t%s\n" % ff.tlink[(e1, e2)]
                    #else: timex_timex_str += tt_str + "\t%s\n" % ff.tlink[(e1, e2)]

                    #n_tt_pairs += 1
                    #if n_tt_pairs % 25 == 0: timex_timex_str += "\n"
                    pass

                else:  #timex-event pair
                    pair_order = "te"
                    (eidx2, tid2, _, eclass2, _, _) = ff.entities[e2]
                    (token2, sentid2, lemma2, pos2, mainvb2, entity2, chunk2,
                     conn2, mainpos2, tense2, aspect2, pol2,
                     supersense2) = ff.tokens[tid2]
                    (pos_path2, pos_pol2) = ff.getPOSPath(
                        tid2
                    )  #get POS path (for verb, noun and adj are based on dependent verb) and polarity from POS

                    (dep_rel, dep_order) = ("O", "O")
                    (dep_path, path_order) = ("O", "O")
                    if not dct1:
                        for i in range(int(tid_start1), int(tid_end1) + 1):
                            (dep_rel,
                             dep_order) = ff.getDependency(tid2, str(i))
                            if dep_rel != "O": break
                            (dep_path,
                             path_order) = ff.getDependencyPath(tid2, str(i))
                            if dep_path != "O": break

                    (sent_distance, ent_distance,
                     ent_order) = ff.getDistance(sentid1, sentid2, eidx1,
                                                 eidx2)
                    (temp_conn1, temp_conn_pos1) = ff.getTemporalConnective(e2)
                    (temp_conn2, temp_conn_pos2) = ff.getTemporalConnective(e1)
                    (temp_signal1, temp_signal_pos1) = ff.getTemporalSignal(e2)
                    (temp_signal2, temp_signal_pos2) = ff.getTemporalSignal(e1)

                    timex_rule = ff.getTimexRule(e1)
                    reltype_rule = ff.getRelTypeRule(temp_signal2, pair_order,
                                                     eclass2, timex_type1,
                                                     timex_value1, e1)

                    et_str = ""
                    et_str += "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" % \
                        (e2, e1, pair_order, token2, token1, lemma2, lemma1, mainpos2, chunk2, sent_distance, ent_distance, ent_order, dep_rel, dep_order, dep_path, path_order, mainvb2, eclass2, tense2, aspect2, pol2, timex_type1, timex_value1, dct1, pos_path2, pos_pol2, temp_signal2, temp_signal_pos2, temp_signal1, temp_signal_pos1, temp_conn2, temp_conn_pos2, temp_conn1, temp_conn_pos1, timex_rule)
                    if classification == "bin":
                        if ff.tlink[(e1, e2)] != "NONE": rel_type = "REL"
                        else: rel_type = ff.tlink[(e1, e2)]
                        et_str += "\t%s" % rel_type

                        if et_opt == "dct" and dct1:
                            event_timex_dct += et_str + "\tREL\n"
                        elif et_opt == "non-dct" and not dct1:
                            event_timex_non_dct += et_str + "\tREL\n"
                        elif et_opt == "dct-main" and dct1:
                            if mainvb2: event_timex_dct += et_str + "\tREL\n"
                            else: event_timex_str += et_str + "\n"
                        elif et_opt == "main":
                            if mainvb2: event_timex_main += et_str + "\tREL\n"
                            else: event_timex_str += et_str + "\n"
                        elif et_opt == "rule":
                            if reltype_rule != "O":
                                event_timex_main += et_str + "\t" + reltype_rule + "\n"
                            else:
                                event_timex_str += et_str + "\n"
                        else:
                            event_timex_str += et_str + "\n"
                    elif classification == "rel":
                        if True:
                            #if ff.tlink[(e1, e2)] != "NONE":
                            #if ff.tlink[(e1, e2)] != "NONE" and ff.tlink[(e1, e2)] != "ENDED_BY" and ff.tlink[(e1, e2)] != "BEGUN_BY":

                            #for QA-TempEval: DURING and IDENTITY are mapped to SIMULTANEOUS, IBEFORE/IAFTER are mapped to BEFORE/AFTER
                            #                 BEGUN_BY, ENDED_BY and INCLUDES are mapped to BEGINS, ENDS and IS_INCLUDED
                            rel_type = ff.getInverseRelation2(ff.tlink[(e1,
                                                                        e2)])
                            #if rel_type == "DURING" or rel_type == "DURING_INV" or rel_type == "IDENTITY": et_str += "\t%s" % "SIMULTANEOUS"
                            if rel_type == "IBEFORE":
                                et_str += "\t%s" % "BEFORE"
                            elif rel_type == "IAFTER":
                                et_str += "\t%s" % "AFTER"
                            elif rel_type == "BEGINS" or rel_type == "ENDS" or rel_type == "INCLUDES":
                                et_str += "\t%s" % ff.getInverseRelation(
                                    ff.tlink[(e1, e2)])
                            elif rel_type == "IS_INCLUDED" and timex_type1 == "DURATION":
                                et_str += "\t%s" % "MEASURE"  #for NewsReader
                            else:
                                et_str += "\t%s" % rel_type

                            #et_str += "\t%s" % ff.tlink[(e1, e2)]
                            if et_opt == "rule":
                                if reltype_rule != "O" and sent_distance == 0:
                                    event_timex_main += et_str + "\t" + reltype_rule + "\n"
                                else:
                                    event_timex_str += et_str + "\n"
                            else:
                                event_timex_str += et_str + "\n"
                    else:
                        event_timex_str += et_str + "\t%s\n" % ff.tlink[
                            (e1, e2)]

                    n_et_pairs += 1
                    #if n_et_pairs % 25 == 0: event_timex_str += "\n"

            else:
                (eidx1, tid1, _, eclass1, _, _) = ff.entities[e1]
                (token1, sentid1, lemma1, pos1, mainvb1, entity1, chunk1,
                 conn1, mainpos1, tense1, aspect1, pol1,
                 supersense1) = ff.tokens[tid1]
                (pos_path1, pos_pol1) = ff.getPOSPath(
                    tid1
                )  #get POS path (for verb, noun and adj are based on dependent verb) and polarity from POS

                if ff.isTimex(e2):  #event-timex pair
                    pair_order = "et"
                    (eidx2, tid_start2, tid_end2, timex_type2, timex_value2,
                     dct2) = ff.entities[e2]
                    if dct2: sentid2 = "O"
                    else:
                        (_, sentid2, _, _, _, _, _, _, _, _, _, _,
                         _) = ff.tokens[tid_start2]
                    (lemma2, token2) = ff.getLemmaTokenTimex(e2)

                    (dep_rel, dep_order) = ("O", "O")
                    (dep_path, path_order) = ("O", "O")
                    if not dct2:
                        for i in range(int(tid_start2), int(tid_end2) + 1):
                            (dep_rel,
                             dep_order) = ff.getDependency(tid1, str(i))
                            if dep_rel != "O": break
                            (dep_path,
                             path_order) = ff.getDependencyPath(tid1, str(i))
                            if dep_path != "O": break

                    (sent_distance, ent_distance,
                     ent_order) = ff.getDistance(sentid1, sentid2, eidx1,
                                                 eidx2)
                    (temp_signal1, temp_signal_pos1) = ff.getTemporalSignal(e1)
                    (temp_signal2, temp_signal_pos2) = ff.getTemporalSignal(e2)
                    (temp_conn1, temp_conn_pos1) = ff.getTemporalConnective(e1)
                    (temp_conn2, temp_conn_pos2) = ff.getTemporalConnective(e2)

                    timex_rule = ff.getTimexRule(e2)
                    reltype_rule = ff.getRelTypeRule(temp_signal2, pair_order,
                                                     eclass1, timex_type2,
                                                     timex_value2, e2)

                    et_str = ""
                    et_str += "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" % \
                        (e1, e2, pair_order, token1, token2, lemma1, lemma2, mainpos1, chunk1, sent_distance, ent_distance, ent_order, dep_rel, dep_order, dep_path, path_order, mainvb1, eclass1, tense1, aspect1, pol1, timex_type2, timex_value2, dct2, pos_path1, pos_pol1, temp_signal1, temp_signal_pos1, temp_signal2, temp_signal_pos2, temp_conn1, temp_conn_pos1, temp_conn2, temp_conn_pos2, timex_rule)
                    if classification == "bin":
                        if ff.tlink[(e1, e2)] != "NONE": rel_type = "REL"
                        else: rel_type = ff.tlink[(e1, e2)]
                        et_str += "\t%s" % rel_type

                        if et_opt == "dct" and dct2:
                            event_timex_dct += et_str + "\tREL\n"
                        elif et_opt == "non-dct" and not dct2:
                            event_timex_non_dct += et_str + "\tREL\n"
                        elif et_opt == "dct-main" and dct2:
                            if mainvb1: event_timex_dct += et_str + "\tREL\n"
                            else: event_timex_str += et_str + "\n"
                        elif et_opt == "main":
                            if mainvb1: event_timex_main += et_str + "\tREL\n"
                            else: event_timex_str += et_str + "\n"
                        elif et_opt == "rule":
                            if reltype_rule != "O":
                                event_timex_main += et_str + "\t" + reltype_rule + "\n"
                            else:
                                event_timex_str += et_str + "\n"
                        else:
                            event_timex_str += et_str + "\n"
                    elif classification == "rel":
                        if True:
                            #if ff.tlink[(e1, e2)] != "NONE":
                            #if ff.tlink[(e1, e2)] != "NONE" and ff.tlink[(e1, e2)] != "ENDED_BY" and ff.tlink[(e1, e2)] != "BEGUN_BY":

                            #for QA-TempEval: DURING and IDENTITY are mapped to SIMULTANEOUS, IBEFORE/IAFTER are mapped to BEFORE/AFTER
                            #                 BEGUN_BY, ENDED_BY and INCLUDES are mapped to BEGINS, ENDS and IS_INCLUDED
                            rel_type = ff.tlink[(e1, e2)]
                            #if rel_type == "DURING" or rel_type == "DURING_INV" or rel_type == "IDENTITY": et_str += "\t%s" % "SIMULTANEOUS"
                            if rel_type == "IBEFORE":
                                et_str += "\t%s" % "BEFORE"
                            elif rel_type == "IAFTER":
                                et_str += "\t%s" % "AFTER"
                            elif rel_type == "BEGINS" or rel_type == "ENDS" or rel_type == "INCLUDES":
                                et_str += "\t%s" % ff.getInverseRelation(
                                    ff.tlink[(e1, e2)])
                            elif rel_type == "IS_INCLUDED" and timex_type2 == "DURATION":
                                et_str += "\t%s" % "MEASURE"  #for NewsReader
                            else:
                                et_str += "\t%s" % rel_type

                            #et_str += "\t%s" % ff.tlink[(e1, e2)]
                            if et_opt == "rule":
                                if reltype_rule != "O" and sent_distance == 0:
                                    event_timex_main += et_str + "\t" + reltype_rule + "\n"
                                else:
                                    event_timex_str += et_str + "\n"
                            else:
                                event_timex_str += et_str + "\n"
                    else:
                        event_timex_str += et_str + "\t%s\n" % ff.tlink[
                            (e1, e2)]

                    n_et_pairs += 1
                    #if n_et_pairs % 25 == 0: event_timex_str += "\n"

                else:  #event-event pair
                    (eidx2, tid2, _, eclass2, _, _) = ff.entities[e2]
                    (token2, sentid2, lemma2, pos2, mainvb2, entity2, chunk2,
                     conn2, mainpos2, tense2, aspect2, pol2,
                     supersense2) = ff.tokens[tid2]
                    (pos_path2, pos_pol2) = ff.getPOSPath(
                        tid2
                    )  #get POS path (for verb, noun and adj are based on dependent verb) and polarity from POS

                    (sent_distance, ent_distance,
                     ent_order) = ff.getDistance(sentid1, sentid2, eidx1,
                                                 eidx2)
                    if ent_order == "reverse":
                        (dep_rel, dep_order) = ff.getDependency(tid2, tid1)
                        (dep_path,
                         path_order) = ff.getDependencyPath(tid2, tid1)
                    else:
                        (dep_rel, dep_order) = ff.getDependency(tid1, tid2)
                        (dep_path,
                         path_order) = ff.getDependencyPath(tid1, tid2)
                    samePOS = (pos1 == pos2)
                    sameClass = (eclass1 == eclass2)
                    sameTense = (tense1 == tense2)
                    sameAspect = (aspect1 == aspect2)
                    samePol = (pol1 == pol2)
                    (temp_conn1, temp_conn_pos1) = ff.getTemporalConnective(e1)
                    (temp_conn2, temp_conn_pos2) = ff.getTemporalConnective(e2)
                    (temp_signal1, temp_signal_pos1) = ff.getTemporalSignal(e1)
                    (temp_signal2, temp_signal_pos2) = ff.getTemporalSignal(e2)

                    if ent_order == "reverse":
                        if (e2, e1) in ff.clink: clink = ff.clink[(e2, e1)]
                        else: clink = "O"
                    else:
                        if (e1, e2) in ff.clink: clink = ff.clink[(e1, e2)]
                        else: clink = "O"

                    coref = "O"
                    if (e1, e2) in ff.coref_events or (e2,
                                                       e1) in ff.coref_events:
                        coref = "COREF"

                    ee_str = ""
                    if ent_order == "reverse":
                        ee_str += "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" % \
                            (e2, e1, token2, token1, lemma2, lemma1, mainpos2+"-"+mainpos1, chunk2+"-"+chunk1, sent_distance, ent_distance, ent_order, dep_rel, dep_order, dep_path, path_order, str(mainvb2)+"-"+str(mainvb1), eclass2+"-"+eclass1, tense2+"-"+tense1, aspect2+"-"+aspect1, pol2+"-"+pol1, samePOS, sameClass, sameTense, sameAspect, samePol, pos_path2+"-"+pos_path1, pos_pol2+"-"+pos_pol1, temp_signal2, temp_signal_pos2, temp_signal1, temp_signal_pos1, temp_conn2, temp_conn_pos2, temp_conn1, temp_conn_pos1, clink, coref)
                    else:
                        ee_str += "%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" % \
                            (e1, e2, token1, token2, lemma1, lemma2, mainpos1+"-"+mainpos2, chunk1+"-"+chunk2, sent_distance, ent_distance, ent_order, dep_rel, dep_order, dep_path, path_order, str(mainvb1)+"-"+str(mainvb2), eclass1+"-"+eclass2, tense1+"-"+tense2, aspect1+"-"+aspect2, pol1+"-"+pol2, samePOS, sameClass, sameTense, sameAspect, samePol, pos_path1+"-"+pos_path2, pos_pol1+"-"+pos_pol2, temp_signal1, temp_signal_pos1, temp_signal2, temp_signal_pos2, temp_conn1, temp_conn_pos1, temp_conn2, temp_conn_pos2, clink, coref)
                    if classification == "bin":
                        if ff.tlink[(e1, e2)] != "NONE": rel_type = "REL"
                        else: rel_type = ff.tlink[(e1, e2)]
                        ee_str += "\t%s" % rel_type

                        if ee_opt == "main":
                            if mainvb1 or mainvb2:
                                event_event_main += ee_str + "\tREL\n"
                            else:
                                event_event_str += ee_str + "\n"
                        elif ee_opt == "coref":
                            if coref == "COREF":
                                event_event_main += ee_str + "\tSIMULTANEOUS\n"  #NewsReader and QA-TempEval no IDENTITY
                                #if coref == "COREF": event_event_main += ee_str + "\tIDENTITY\n"
                            else:
                                event_event_str += ee_str + "\n"
                        else:
                            event_event_str += ee_str + "\n"

                    elif classification == "rel":
                        if True:
                            #if ff.tlink[(e1, e2)] != "NONE":
                            #if ff.tlink[(e1, e2)] != "NONE" and ff.tlink[(e1, e2)] != "BEGINS" and ff.tlink[(e1, e2)] != "BEGUN_BY" and ff.tlink[(e1, e2)] != "ENDS" and ff.tlink[(e1, e2)] != "ENDED_BY" and ff.tlink[(e1, e2)] != "IAFTER" and ff.tlink[(e1, e2)] != "IBEFORE":

                            #for QA-TempEval: DURING and IDENTITY are mapped to SIMULTANEOUS, IBEFORE/IAFTER are mapped to BEFORE/AFTER
                            rel_type = ff.tlink[(e1, e2)]
                            if ent_order == "reverse":
                                rel_type = ff.getInverseRelation2(rel_type)
                            #if rel_type == "DURING" or rel_type == "DURING_INV" or rel_type == "IDENTITY": ee_str += "\t%s" % "SIMULTANEOUS"
                            if rel_type == "IBEFORE":
                                ee_str += "\t%s" % "BEFORE"
                            elif rel_type == "IAFTER":
                                ee_str += "\t%s" % "AFTER"
                            else:
                                ee_str += "\t%s" % rel_type

                            #event_event_str += ee_str + "\t%s\n" % ff.tlink[(e1, e2)]

                            if ee_opt == "coref":
                                if coref == "COREF":
                                    event_event_main += ee_str + "\tSIMULTANEOUS\n"  #NewsReader and QA-TempEval no IDENTITY
                                    #if coref == "COREF": event_event_main += ee_str + "\tIDENTITY\n"
                                else:
                                    event_event_str += ee_str + "\n"
                            else:
                                event_event_str += ee_str + "\n"

                    else:
                        event_event_str += ee_str + "\t%s\n" % ff.tlink[
                            (e1, e2)]

                    n_ee_pairs += 1
                    #if n_ee_pairs % 25 == 0: event_event_str += "\n"

    for (e1, e2) in ff.tmxlink:
        timex_timex_str += e1 + "\t" + e2 + "\t" + ff.tmxlink[(e1, e2)] + "\n"

    #print event_event_str
    #print event_timex_str
    #print timex_timex_str

    if pair_type == "ee":
        if ee_opt == "main": return (event_event_main, event_event_str)
        elif ee_opt == "coref":
            #the rest of the corefer-events not in tlinks? label them as SIMULTANEOUS?
            for (coev1, coev2) in ff.coref_events:
                if (coev1, coev2) not in ff.tlink and (coev2,
                                                       coev1) not in ff.tlink:
                    print coev1 + "\t" + coev2 + "\tSIMULTANEOUS"  #NewsReader and QA-TempEval no IDENTITY
                    #print coev1 + "\t" + coev2 + "\tIDENTITY"
            return (event_event_main, event_event_str)
        else:
            return event_event_str
    elif pair_type == "et":
        if et_opt == "dct": return (event_timex_dct, event_timex_str)
        elif et_opt == "non-dct": return (event_timex_non_dct, event_timex_str)
        elif et_opt == "dct-main": return (event_timex_dct, event_timex_str)
        elif et_opt == "main": return (event_timex_main, event_timex_str)
        elif et_opt == "rule": return (event_timex_main, event_timex_str)
        else: return event_timex_str
    elif pair_type == "tt": return timex_timex_str