Stf
[医][=serum thymus factor]血清胸腺因子
🗣️ 情景例句
If you can't handle this job by yourself, I'm just a phone call away.
若你不能自己处理这件事的话，就打个电话给我吧。
He's an American.
他是美国人。
Who was second? Who was third?
谁是第二？谁是第三？