---I'm sorry,but it's my seat.

---           I didn't know it's yours.

What if

I beg your pardon

That's all right

What for

考查交际用语。句意：---对不起，这是我的座位。---请原谅。我不知道这是你的。A. What if如果.....将会怎么样；B. I beg your pardon. 对不起，请原谅；C.That's all right没关系；D. What for为什么。根据"Idon't know it's yours."可知坐了别人的座位，请求别人原谅。故选B项。

---It's burning hot today,isn't it?

---Yes,_____yesterday.

So was it

So it was

So it is

So is it

句意：“今天太热了，是不是？”“是呀，昨天也一样”。如果表示前面所说的肯定情况也适合于另一者，要用“so+助动词/情态动词/系动词+主语”。

In our daily life, everyone fails every now and then. It is how you             that makes a difference.

react

replace

rely

request

考查动词词义辨析。句意：在我们的日常生活中，每个人都会时不时地失败，你对失败如何反应才是关键。A. react反应；B. repalce取代，代替；C. rely 依靠，依赖；D.request要求；根据“n our daily life, everyone fails every now and then”，应是“怎样做出反应”。故选A项。