---Do you know if Dr White will come for dinner this evening?---No.but I think he if he busy．( )A．will come.doesn'tB．comes.isn'tC．will come.isn'tD．comes.doesn't 题目和参考答案——青夏教育精英家教网—

题目内容

8．---Do you know if Dr White will come for dinner this evening？
---No，but I think he ______ if he ______busy．（　　）

	A．	will come，doesn't		B．	comes，isn't
	C．	will come，isn't		D．	comes，doesn't

分析 ---你知道怀特博士是否今晚会回来吃晚饭？
---不，但是我认为如果他不忙他就会来．

解答答案：C．think后紧跟省略了that的宾语从句，主句是一般现在时，从句时态不受限制，if引导的是条件状语从句，遵循主将从现的规则，主句一般将来时will+动词原形，从句一般现在时，主语he故is，故答案是C．

点评一、如果主句是将来时或表示将来含义时，那么条件和时间状语从句多用一般现在时如：When I grow up，I will be a nurse and look after patients/I want to be a nurse and look after patients．我长大后要当一名护士，照顾病人．二、如果主句是祈使句，那么从句通常要用一般现在时如：Don't laugh at me when I make a mistake．我犯错误的时候不要笑话我．三、如果主句是含有情态动词的一般现在时，根据需要从句多用一般现在时如：You should be quiet when you are in the reading room在阅览室时应保持安静．