丢三落四 forgetful
miss this and that
forget this, that and the other
there is always sth. missing
scatterbrained
- 把你娶媳妇应办的事早些料理料理, 免得到时丢三落四的。
- 最近我总是丢三落四。
I have been forgetful lately. - 他老是这么丢三落四的。你看,又把房门钥匙锁在屋子里了。
Look, he's locked his key inside his room again.