一も二も無く[ichimonimonaku] unhesitatingly
一言二言[hitokotofutakoto] a word or two
一石二鳥[issekinichou] killing two birds with one stone
一二に及ばず[ichininioyobazu] right away
一姫二太郎[ichihimenitarou] It's good to have a girl first and then a boy

うり二つ[urifutatsu] as alike as two melons (two peas in a pod)
黄道十二宮[koudoujuunikyuu] twelve signs of the zodiac
二度[futatabi] again
最小二乗法[saishounijouhou] least-squares method
三十二分音符[sanjuunibuonpu] 32nd note

彼の人[anohito] he
殆どの人[hotondonohito] most people
アメリカ人[amerikajin] American person
クローン人間[kuroonningen] (human) clone
シゾイド人間[shizoidoningen] schizoid person

ドイツ人[doitsujin] German person
ベトナム人[betonamujin] Vietnamese (person)
ペルシア人[perushiajin] Persian person
ユダヤ人[yudayajin] Jew
愛人[aijin] lover

御前[omai] you (formerly honorific, now sometimes derog. term referring to an equal or inferior)
御前さん[omaesan] you
已前[izen] ago
以前に[izenni] ago
一人前[ichininmae] becoming adult

一人前になる[ichininmaeninaru] to come of age
一昔前[hitomukashimae] long ago
一歩前進[ippozenshin] (a) step forward
駅前[ekimae] in front of station
駅前通り[ekimaedoori] street in front of station