I'm really angry with him!
我对他很生气！
be angry with sb
对某人感到生气
Are you angry with me for some reason?
你是因为某个原因生我的气吗？
be angry about sth
对某事感到生气
I was very angry about the rumours.
我对这些谣言感到生气。

A:Why are you so depressed,Tommy?
汤米，你的情绪好像很低落。怎么了？
B:Nothing.I'm just tired.
没什么。我就是有点儿累。
A:Come on,Tommy.You can tell me!
别这样，汤米。你有什么事情可以告诉我。
B:The boss gave me such a lot of work to do!I was working until 10 o'clock yesterday.And it has not been finished!
老板给了我特别多的活。昨天晚上我又工作到了十点。问题是，到现在还没有做完。
A:Why don't you talk to your boss?
你为什么不和你老板谈谈呢？
B:I have talked to him.But he just said he couldn't find another person to help me.I'm really angry with him.
我跟他谈了。可他说他找不到别人来帮我。我对他很生气。
A:Tommy,just relax.I think your boss understands how hard you are working.
汤米，放轻松点。我相信你的老板知道你工作得多么辛苦。
B:I hope so.
但愿如此。