/'ɔ:lsəʊ; `ɔlso/
adv (not used with negative vs 不与否定式动词连用) in addition; besides; too 而且; 还; 也
*She speaks French and German and also a little Russian. 她会说法语, 德语, 还会说一点儿俄语.
* He is young and good-looking, and also very rich. 他又年轻又漂亮, 而且还很富有.
* I teach five days a week and I also teach evening classes. 我每星期教五天, 而且还教晚上的课.
* She not only plays well, but also writes music. 她不仅很会演奏, 而且还会作曲.

NOTE ON USAGE 用法
*Also, too and as well indicate that the word or part of the sentence that they are specially linked to has been added to something previously mentioned. *also, too, as well均指句中有关词语与前面提到的事物相结合或相一致. They differ in degree of formality and position in the sentence. 这三个词语的雅俗程度和在句中的位置有所不同. Also is more formal and usually comes before the main verb (but after `be' if this is the main verb) *also含较庄重色彩, 通常用于主要动词之前（但若主要动词是be, 则置于其後）
*I've met Jane and I've also met her mother. 我已见到简, 我也见到了她的母亲.
* He speaks French and he also writes it. 他会说法语也会写法文.
* She was rich. She was also selfish. 她很富. 她也很自私. Too and as well are less formal and usually come at the end of the clause *too和as well较为通俗, 通常用于从句的句尾
*I've read the book and I've seen the film as well/too. 我看过这本书, 也看过这部电影. In negative sentences, not...either is used to indicate addition 在否定句中, 用 not...either表示这种增加的成分
*They haven't phoned and they haven't written either. 他们没来过电话, 而且也没来过信.

adv
[Language: Old English;Origin: eallswa, from eall 'completely' + swa 'so']
in addition to something else that you have mentioned
　Information is also available on women's health care.
　She sings beautifully and also plays the flute and piano.
　The system was not only complicated but also ineffective.
used to say that the same thing is true about another person or thing
　My girlfriend was also called Helen.

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WORD CHOICE: also, too, as well, either
also, too and as well can be used in many of the same contexts : She's a valued colleague, and a great friend too OR and a great friend as well OR and also a great friend.
also is the most formal and the most likely to be used in formal writing such as reports.
as well is the most informal and the most likely to be used in speech.
!! too is never used at the beginning of a clause. Also is not usually used at the end of a clause : Smoking makes you ill. It costs a lot too/as well OR It's also expensive OR Also, it's expensive.
Use either when you are adding another negative fact : Our first attempt didn't work, and our second didn't either (NOT also didn't).

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