Precarburization
预先碳化[渗碳]
🗣️ 情景例句
I'm glad you came. You're welcome any time.
我很高兴你能来。随时都欢迎你们来。
I was sick yesterday,but I'm better today.
我昨天病了，但是我今天好一些了。
Try to look on the bright side of things.
尽量从好的方面看。