挂号

1. 我把那封信挂号寄出了，因为里面有钱。
   I registered the letter because it contain some money.
2. 她一定已经收到包裹了，我是用挂号寄的。
   She must have received the parcel: I sent it by registered post.
3. 信中夹钞票最好寄挂号。
   It's wise to register letters containing banknotes.

号的英语翻译：