一、may well
may well 主要用于加强推测的语气，表示具有较大的可能性。如：
It may well be true. 那很可能是真的。
What you say may well be true. 你说的很可能是事实。
Her grandpa may well be over eighty. 她的祖父可能已有80多岁了。
That may well have been their intention. 这很可能是他们的意图。
【注】may well 中的 may 也可换成 might 或 could，但语气更不确定。如：
He might well lose his job. 他多半会丢了那份工作。
He might [could] well find that the course is too difficult. 他很可能觉得这门课太难。
请看一道考题：
Liza ______ well not want to go on the trip—she hates traveling.
A. will B. can C. must D. may
分析：may 和 might 后接副词 well 加强语气，意为“很可能”，故选 D。
二、may as well
may as well 主要用于表示提议或劝告，意为“不妨”。如：
I may as well start at once. 我还不妨马上就动身。
If that is the case, I may as well try. 既然如此，我不妨试一试。
Now that you have come you may as well stay. 既然你来了，你就留下。
【注】其中的 may 也可换成 might，但语气更不确定。如：
He may [might] as well come with me. 他还不妨跟我一起来。
It’s not very far, so we may [might] as well go on foot. 那地方不太远，所以我们还是走着去吧。
请看一道考题：
You are here, so you _______ as well give me a hand.
A. can B. should C. need D. may
分析：may [might] as well 用于表示提议，意为“不妨”，故选 D。句意为：你们既然在这儿，不妨就帮我一下。
三、一点提醒
当表示提议或劝告时，may as well 与 might as well 意思相同，但是 might as well 还可将一种不愉快的情况同另一种不愉快的情况作比较，含有抱怨的意味，通常译为“还不如”，此时不能用 may as well。如：
This holiday isn’t much fun; we might as well be back home. 这个假日过得真没意思，我们还不如待在家里。
“What a slow bus this is!” “Yes, we might just as well walk.” “这辆公共汽车开得多慢啊!”“是呀，我们还不如走着去。”
You never listen—I might as well talk to a brick wall. 你一点也不听——我还不如跟墙壁说话呢。
The buses are so expensive these days, so you might as well get a taxi. 最近公共汽车车费很贵，还不如坐出租车去。