but, however, while, although和though用法小结
【观察】阅读下列句子，注意各句中黑体单词的用法。
1. We have made some achievements, but we should be modest.
2. He promised to help me. However, he is busy and hasn’t come.
3. She felt ill. She went to work, however, and tried to concentrate.
4. He said that it was so; he was mistaken, however.
5. You like sports, while I’d rather read.
6. While I understand what you say, I can’t agree with you.
7. Although / Though it was late, she went on working.
8. Tired though he was, he went on working.
9. Although he’s got a good job now, he still complains.
10. She promised to phone. I heard nothing, though.
【归纳总结】
★but与however均可表示转折，意为“但是，然而”，都可以引出表转折意义的句子（句1-句4），但二者用法也有区别：
1. 从语义上看，but所表示的是非常明显的对比，转折的意味较however要强。
2. 从语法上看，but是个并列连词，而however却是个连接副词（句2-句4）。
3. 从语序上看，but总是位于它所引出的分句之首，而however可位于句首、句中或句尾。
4. 从标点上说，but之后一般不使用逗号，但however则通常用逗号与句子其他部分分开。
★连词while的用法
1. 引导表对比关系的并列句，意为“而，然而”（句5）。
2. 引导让步状语从句，意为“虽然，尽管”，多放在句首（句6）。
★although与though的用法
1. although与though用作连词时，意为“虽然，尽管”，引导让步状语从句（句7）。although在大多数情况下可与though通用。但在正式文体中，though可用于一种不以其为首的让步状语从句，这种从句须以形容词等开头，整个从句须置于主句之前（句8），这时although不能替换though。
2. although / though引导从句时，主句不可再使用but, however等，但可出现副词still等（句9）。
3. though可用作副词，意为“可是，不过”，一般放在句末（句10），但although一般不用作副词。
【即学即练】从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。
1. I was glad to meet Jenny again, _____ I didn’t want to spend all day with her. (2013新课标全国卷II)
A. but B. and
C. so D. or
2. There’s no way of knowing why one man makes an important discovery _____ another man, also intelligent, fails. (2013新课标全国卷I)
A. since B. if
C. as D. while
3. _____ small, the company has about 1,000 buyers in over 30 countries. (天津2013)
A. As B. If
C. Although D. Once
4. Queen Elizabeth Ⅱ is often thought to be the richest woman in the world. _____, her personal wealth seems rather small. (安徽2012)
A. Besides B. Otherwise
C. However D. Altogether
5. _____ I always felt I would pass the exam, I never thought I would get an A. (湖南2012)
A. While B. Once
C. If D. Until
答案
【即学即练】1-5 ADCCA
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