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

真婿[manko] vagina
ポラロイド写真[poraroidoshashin] Polaroid picture
人生の真っ盛り[isshounomassakari] the noontide of life
猿真似[sarumane] indiscriminate imitation (lit: monkey imitator)
真近[majika] proximity

真際[magiwa] on the verge of
顔写真[kaojashin] photographic portrait
原色写真版[genshokushashinban] tricolor printing
抗真菌[koushinkin] antifungal
殺真菌薬[satsushinkinyaku] fungicide