情景对话：

A: What luck!

真倒霉！

B: What's the matter?

怎么了？

A: When I set foot in the classroom, I found that I forgot my textbook. The teacher happened to ask me to read the text in the class.

踏进教室的大门，我才发现自己忘了带课本。上课时老师又偏偏叫我读课文。

B: Be careful next time.

下次别这么粗心了。

第一，词海拾贝

set foot in

exp. To enter some location. （踏进，走进）

e.g. It wasn't me—I've never set foot in that building before!

不是我——我从来没进过那栋楼！

e.g. If you ever set foot in my house again, I'll have you arrested.

如果你再敢踏进我的房子，我就把你抓起来。

e.g. The judge ordered him never to set foot in her house again.

法官命令他再也不要进她的房子。

e.g. If I had my way I'd never set foot in the damned country again.

要是由着我的话，我永远不会再踏上那个混账国家的土地。

第二，语汇积累

happen to do something/something：碰巧做某事，碰巧遇到某事

e.g. I happen to have an honest partner.

我碰巧有一个忠实的好搭档。

e.g. Don't you wand to know how I happen to know that the whole thing is going to blow?

你不想知道我是怎样碰巧得到了整个案情都将告吹的消息吗？

e.g. If you happen to be passing by, be sure to step in and have a chat.

如果你正好路过的话，请一定进来聊聊。