是不是一个句子中有了动词就不用be动词了呢?
--英语法语规定一个简单句里只能有一个谓语动词.但进行时态,都是由be+V-ing形式构成.如: I am doing my homework now. am 是BE动词,而do是实义动词.
在特殊疑问句(没有原陈述句的情况下选择)是不是也是上面那个办法,
--在疑问句里,语法规定要借有助动语引导句子提问,有be动语,情态动词(can, could, should would may...)在句中是,直接借用它们放在句首引导疑问句;没有它们时,借有do的相应时态引导疑问句,并且谓语动词要改回原型.如 he finished his homework yesterday. 改成疑问句: Did he finish his homework yesterday?