一道名词语法题Doctor Adams explained that not all bacteria_____ harmfula.were b.are c.was D is为什么不选A.用过去时?

一道名词语法题Doctor Adams explained that not all bacteria_____ harmfula.were b.are c.was D is为什么不选A.用过去时? Doctor Adams explained that not all bacteria —— harmful.Doctor Adams explained that not all bacteria —— harmful.填的是 are 我想知道这是什么语法点 为什么不填 were,能不能给我这个语法的知识和例句罗列下. 一道高中语法题 一道高中语法题 英语 请教一道GMAT语法题 一道SAT OC 语法题> 一道高中语法题vbj 副词可以修饰名词?一道Sat语法题一道sat语法题the hilly terrain,the final miles of the racecourse for the other runners and .答案是无错误那exceptionally adv岂不是修饰hilly terrain n 简述名词语法特点 名词复数（题）woman doctor的复数形式理由为什么只有women作复数？ 一道sat的语法题,解释 问一道题 详细语法解释 ,英语专四语法一道 第三题 专四语法一道,第4题, 一道sat上的语法题 一道英语句型转换题 You have to go to the doctor tomorrow.(改为祈使句）__ __the doctor tomorrow. 分析语法成分,为什么his son John Adams之后还有逗号整句话是这样的Two presidents of the USA,John Adams and his son John Adams,were born in Quincy, 请教大家一道专四语法题____we are having these days!A what a lovely weatherB what lovely weathersC what lovely weatherD what lovely a weather为什么不是C,weather是不可数名词阿