ちょっと一杯[chottoippai] let's have a quick drink
ばつ一[batsuichi] being once divorced
一向[hitaburu] nothing but
サラダ一皿[saradahitosara] plate of salad

安全第一[anzendaiichi] safety first
一か八か[ichikabachika] sink or swim
一っ走り[hitoppashiri] spin (as in 'take a car for a spin')
一つ一つ[hitotsuhitotsu] one-by-one

其れ共[soretomo] or
と共に[totomoni] together with
ドイツ民主共和国[doitsuminshukyouwakoku] German Democratic Republic (i.e. former East Germany)
ドイツ連邦共和国[doitsurenpoukyouwakoku] Federal Republic of Germany (former West Germany)
ビジネススクール入学共通試験[bijinesusukuurunyuugakukyoutsuushiken] business school entrance test

欧州共同体[oushuukyoudoutai] European Community
共に[tomoni] together
共営[kyouei] joint management
共栄[kyouei] mutual prosperity

これと同じ[koretoonaji] the same as this
と同じ様に[toonajiyouni] in the same way as
安定同位体[anteidouitai] stable isotope
異句同音[ikudouon] in concert
異口同音に[ikudouonni] in one voice

異同[idou] difference
一口同音[ikkudouon] reading in unison
一視同仁[isshidoujin] loving every human being with impartiality
一心同体[isshindoutai] being one in body and soul
一同[ichidou] all present

お願い致します[onegaiitashimasu] please
如何致しまして[douitashimashite] you are welcome
一致[icchi] coincidence
一致点[icchiten] point of agreement
引致[inchi] arrest

雅致[gachi] artistry
共同一致[kyoudouicchi] unanimous cooperation
極致[kyokuchi] culmination
言行一致[genkouicchi] acting up to one's words
合致[gacchi] agreement