例句：

　　1、He is too young to join the army.

　　他太年輕了,還不能參軍。

　　2、When did you join the air force?

　　你什么時候參加的空軍部隊?

　　3、The regular troops of Baden joined the insurgents.

　　巴登的正規(guī)軍參加到起義軍方面來了。

　　4、John joined a football club a few days ago.

　　約翰幾天前加入了一個足球俱樂部。