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

テロ組織[terososhiki] terrorist organization
遺伝因子組替え[ideninshikumikae] recombinant gene splicing
改組[kaiso] reorganization
共済組合[kyousaikumiai] cooperative society
共同組合[kyoudoukumiai] cooperative

協同組合[kyoudoukumiai] cooperative
教養番組[kyouyoubangumi] educational channel
五人組[goningumi] five-family unit
娯楽番組[gorakubangumi] amusement program
骨組[honegumi] skeletal frame