happen to后面是加 be吗还是其他she couldnt leave earlier,becase there happened ---an english test.A to be B to have C to take D to hold请说明你选择的理由,还有正确的是B,但为什么是呢

happen to后面是加 be吗还是其他she couldnt leave earlier,becase there happened ---an english test.A to be B to have C to take D to hold happen to后面是加 be吗还是其他she couldnt leave earlier,becase there happened ---an english test.A to be B to have C to take D to hold请说明你选择的理由,还有正确的是B,但为什么是呢 be an enemy 后面是加to还是of?be a friend 后面加to还是of? be sure to后面是加名词还是动词啊 这个to是介词还是不定式? something/smoebody/nothing等不定代词后面是加to do还是加doing?如：There is always something interesting --------(happen) there.填什么? be inclined to 后面加动名词?---------------还是加动词原型?--------------- be加过去分词后面加to do 还是do? be sensitive后面加什么 是to还是in还是of或者其他 happen to 未发生 happen to be doing 正在发生 happen to hhappen to 未发生happen to be doing 正在发生happen to have done 已发生是这样区别的吗?老师说是.有点不确定 stone的用法 be made of 的用法 the best way to的用法1、stone可不可数?有个句子：The bridge is made of stones.其中的stone 要不要加s 在be made of 后面它是可数的吗?2、be made of 后面加的名词是单数还是复数3 happen to do和happen to be doing有什么区别?区别是?HAPPEN TO BE DOING加的是进行时是吗?那是不是不能加结束性动词（短暂动词）了 be doomed to后面加的是名词还是动词?好像都可以 xiexie! be believed 后面必须加to吗?是固定搭配吗be believed to do sth return是及物动词还是不及物动词,后面加介词to吗? there happened to be 还是there happen to be把happen换成appear呢? be accustomed to后面加do sth.还是doing sth? be honoured to 后面加动词原形,还是ing形式 be used to后面加do还是doing