also,therefore,however用法

also,therefore,however的用法

解题思路： 从意义上来考虑。
解题过程：
also
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。 therefore,
就是因此的意思 后面要紧跟一个句子 后面没有逗号，前后句子意思相关联。却不是因果关系。

I have never been to that city; thereby I don't know much about it.

我从未去过那座城市, 因此对它不怎么熟悉。

therefore: 因为某种原因或结果，所以造成。。。后果。

He was ill, and therefore could not come.

他病了, 所以未能来。
however的用法
however用法详解
一、考点描述however是英语中一个十分重要的考点，近几年来每年的各省考题均有所涉及。请看两道典型真题：
1. You should try to get a good night’s sleep _____ much work you have to do.
A. however B. no matter C. although D. whatever
【分析】答案选A。however作连接副词时，与no matter how相当，后接形容词或副词，意为“无论……”“不管……”。句意是：不管你有多少工作要做，你都应该好好休息一个晚上。
2. He tried his best to solve the problem, _____ difficult it was.
A. however B. no matter C. whatever D. although
【分析】答案选A。因difficult是形容词，修饰形容词要用连接副词however(无论如何，不管多么)，引导一个让步状语从句。
祝期末取得好的成绩！
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)
最终答案：略