I wonder if I should wear a coat or not.

　　我不知道該不該穿外套。

　　Goodness, I wonder if he knows

　　天哪，不知道他是否曉得。

　　I wonder if you could point me in the right direction for the bus station.

　　請問您能指點我到公共汽車站往哪個方向走嗎？

　　I wonder if you can help me.

　　不知您是否能幫我的忙？

　　Nothing more was heard from him so that we began to wonder if he was dead.

　　此后再沒收到他的消息，于是我們開始懷疑他是不是死了。