I can tell you that the prices of cars are a bit high. 我跟你说，汽车的价格有点高。

　　I can tell you what he's going to find. 我可以告诉你他会找到什么。

　　I can't tell you how sorry I am. 真不知道怎么表达我的歉意。

　　I really need to make some money fast.  我非常需要一些救济的钱。

　　I can't tell you how to make money.  我可不能告诉你怎么赚钱。