▲also用于实义动词之前
They also agree with me.
I also began to be interested in crickets.
▲also用于be动词之后
I was also there.
He is also an American.
▲also用于第一个助动词之后
His sister has also gone to town.
The leisure center has also proved uneconomic. 
▲also有时放在句首
Also, some students were tempted to add written comment of their own throughout the paper. 
I thought it was the perfect answer. Also, Tony and I had never done a historical subject.
▲also不能放在句末 
但是,赵振才教授在他的《英语常见问题解答大词典》中列举了美国英语关于also放在句末的例子。
I must buy some bread also.
They know him and I know him also.

The son had gone also.
1. 属正式用词，主要用于肯定句或疑问句，一般不用于否定句 (否定句可用 either)，它在句中通常放在实义动词之前，特殊动词 (动词be、情态动词、助动词)之后，有时也放在整个谓语前面或放在句首或句尾 (较少见，且多半是因为强调之故)。如：I’ve also read the book. 我也读过这本书。This room was also dirty. This room alsowas dirty. This room was dirty also.
Also this room wasdirty. 这个房间也很脏。
2. 有时由于 also 位置不同，可能会导致句子含义不同。如：We alsoregard him as a great writer today. 我们也 (同别人一样)把他看成当今伟大的作家。We regard also him as a great writertoday. 我们把他 (We regard also him as a great writertoday. 也看成当今伟大的作家。
We regardhim as a great writer also today. 我们仍 (同其它时候一样)把他看成当今伟大的作家。
3. 在简略答语中，习惯上不用3.also, 如一般不说 I also, 但可说Metoo, You too等之类的。如：A：I’m tired. 我累了。B：Me too. 我也是。
B：I also. (误)

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