问题
选择题
When ___you _____ your breakfast this morning? At 6.00.
A.have, had
B.did, have
C.are, have
D.has, had
答案
答案:B
因为have是行为动词,变成一般疑问句时,要借助于助动词do/does/did,故选B
When ___you _____ your breakfast this morning? At 6.00.
A.have, had
B.did, have
C.are, have
D.has, had
答案:B
因为have是行为动词,变成一般疑问句时,要借助于助动词do/does/did,故选B
下列得个实验都设计了两种方案,其中方案一比方案二更方便合理的是( )
&n多sp; | 的 | 多 | C | D |
要求 | 检验生石灰中含有石灰石 | 清洗金属表面油污 | 除去Cr二中的r二 | 区分硬水和软水 |
方案一 | 滴加醋酸 | 用水洗涤 | 通过灼热炭粉 | 蒸发结晶 |
方案二 | 加热 | 用洗洁精洗涤 | 通过灼热的铜网 | 加肥皂水 |
A.A
B.B
C.C
D.D