未来进行式 (will be + V-ing)

未来某点或某段时间将要进行的动作

What will you be doing at about three tomorrow afternoon?

明天下午三点左右，你会在做什么？

I will probably be swimming this time tomorrow.

明天这个时候我可能在游泳。

Don't call me at four because I will be studying in the library at that time.

不要在四点钟时打电话给我，因为那个时候我会在图书馆看书。

未来完成式 (will + have + p.p.)

未来某点或某段时间将会完成的动作

My parents will have been married for 30 years this December.

到今年11月我父母结婚就30年了。

By the time you read this letter, I will already have left for the US.

你看到这封信的时候，我将已经动身前往美国了。

The traffic is terrible. We're going to be late.

By the time we get to the airport, your mother's plane will probably have already arrived, and she will be wondering where we are.

到我们到达机场的时候，你妈妈的飞机可能已经到了，她会奇怪我们到哪儿去了。