R.d.a.
[医] 右背前(胎位)
🗣️ 情景例句
Hi, Betty. I'll be at five five five...seventeen twenty.
好 Betty 我的号码是555-1720。
I know the boy whose father is a policeman.
我知道那个男孩的父亲是警察。
Finding planets is proving hard enough, but finding life on them will prove infinitely more difficult.
寻找行星证明相当困难，但是要在行星上发现生命会变得无比艰难。