also, as well, too 与 either 这几个词语意思相同，但用法稍有不同。
(1) ①also较常用在书面英语中，口语中不如too, as well常用。该词不常用在句末，常与动词放在一起(主要动词前，助动词后)，强调时放在句末。
- You must also buy some gas cylinders.
你还必须买一些煤气罐。 - I've also read his other plays.
我还看了他的其他剧本。 - He's made up his mind to go abroad, and I also .
他打定主意出国，我也是。 - The son had gone also .
儿子也去了。
②also有时也放在句首。
- Also, some students were tempted to add written comments of their own throughout the paper.
还有，一些学生受诱使在整张报纸上加上自己的书面评语。
③有时可将also置于整个谓语前。
- This room also was bathed in sunshine.
这个房间也沐浴在阳光中。
(2) as well和too 通常用在句末。
- She not only sings; she plays the piano as well (she also plays the piano).
她不仅唱歌，也弹奏钢琴。 - I was in Germany last summer too .
去年夏天，我也在德国。
(3) too 多用于肯定句，意为“也，同样地”。
- I'll go there too .
我也将去那里。 - They got the work done quickly, and well too .
他们把这工作做得很快，也做得很好。
(4) too可以直接放在主语之后(as well不可)，用在比较正式的场合。
- You, too , may have a try.
你也可以尝试一下。
(5) too还可作“太，过分”解。
- His box is much too big.
他的箱子太大了。 - You've given me three copies too many/too few.
你多/少给了我三份。
＊在日常口语中，too常用在简略式回答中的宾格代词之后。
- A: I've got an idea!
我有了个主意！
B: Me too !
我也有了！
＊在较正式的场合则说：“So have I !”或“I have too!”
(6) too又有“(简直) 太……，非常……”之意，等于very。
- You're really too kind.
你真是太好了。 - I'm not too well these days.
我这些天身体不太好。
(7) all too有“太……”之意，含有惋惜的意味。
- Jack had snatched a short holiday from his work to come here. He said it ended all too soon.
杰克从工作中抓住一个休短假的机会来到这儿。他说这假期结束得太快了。
(8) none too意为“一点也不太……”。
There's only half an hour left; we're none too early for the train.
只剩下半小时了，我们赶火车一点也不太早。
(9) quite too意为“……极了；再……也不过了”。
- It was quite too delightful.
真是太愉快了。 - It was quite too bad!
太糟了!
(10) as well意思是“同样地，和前者一样地”，根据情况，可以指主语，也可以指句子的其他部分。
- John teaches skiing as well .
＊这句话在口语中，如强调主语，则表示：
Some other person teaches skiing, so does John.
约翰和其他教练一样，也教滑雪。
＊如强调teaches，则表示：
John not only does other things, but he teaches skiing.
约翰不仅做些其他事情，还教滑雪。
＊如强调skiing，则表示：
John not only teaches other things, but he teaches skiing.
约翰不仅教其他东西，他还教滑雪。
(11) either 用于否定句，意为“也(不) ……”。
- If you do not dance, I shall not either. (Neither shall I.)
如果你不跳舞，我也不跳。 - I myself don't want to go, and I don't want you to go, either .
我本人不想去，也不想叫你去。 - I don't want candy, and I don't want boots, either .
我不要糖果，也不要靴子。
