1) but表示转折,while表示对比。 Some people love cats, while others hate them.
典型例题 --- Would you like to come to dinner tonight? --- I d like to, ___ I m too busy. A. and B. so C. as D. but 答案D。but与前面形成转折,符合语意。而表并列的and, 结果的so,原因的as都不符合句意。
2) not…but… 意思为"不是……而是……" not 和but 后面的用词要遵循一致原则。 They were not the bones of an animal, but (the bones) of a human being.
比较and和or
1) 并列结构中,or通常用于否定句,and用于肯定句。
2) 但有时and 也可用于否定句。请注意其不同特点: There is no air or water in the moon. There is no air and no water on the moon. 在否定中并列结构用or 连接,但含有两个否定词的句子实际被看作是肯定结构,因此要用and。
典型例题 ---I don t like chicken ___ fish. ---I don t like chicken, ___ I like fish very much. A. and; and B. and; but C. or; but D. or;and 答案C。否定句中表并列用or, but 表转折。
判断改错: (错) We will die without air and water. (错) We can t live without air or water. (对) We will die without air or water. (对) We can t live without air and water.