高中关于时态的英语选择题求解！

Question

（B）I'm afraid there's no more bread. We _ it all last night. In any case , it _stale.
A.were eating , went B.ate , was going C,have eaten , went D.had eaten , had gone
(A) The terrorists_ with the government officials although they hadn't given up.
A.were already negotiating B.already negotiate C.have already negotiated D.have already been negotiating
(B)Although I know Picasso was one of the greatest artists of his time ,I still _ his patintings except for those patinted during his Blue Period.
A.don't ever enjoy B.haven't ever enjoyed C.am not ever enjoying D. hadn't ever enjoyed
(B)Until now research and treatment for overweight _ on drugs to decrease appetite and surgery.
A.focused B.have focused C.are focesing D.were focusing
(A)Competition for admission to the country's top private schools _ tough since few public schools can compare favorably with private schools.
A. has always been B.is always been C.had always been D.was always
(C)As hehas met the company's qualifications, he _ in an office as a junior clerk.
A.will soon have worked B.shall soon work C.will soon be working D. would soon be working
(A)By the end of the 18th century , the city 's population _ about two million.
A.was B.were C.had been D.being

求选择题理由，ABCD都要！！谢谢！

Answer 1

第一题D
析：题目翻译（意译）：我恐怕面包已经没有了，我们昨晚就吃完了，即使有也不新鲜了。第一空的时态为过去完成时，答案A第一空时态不对，直接pass；答案BC时态都不对；故选D。
第二题C
析：题目翻译：恐怖分子已经和政府官员谈判了，尽管他们还没投降。考点：although引导词主谓一致。根据lthough they hadn't given up，排除选项A、B；根据语义选择C。
第三题A
析：考点同上；
第四题A
析：题目翻译：直到现在对超重的研究和治疗都聚焦在药物降低食欲和手术上。考点：until引导的时态要倒退一个时态。根据语义，直到现在……一直……，那么时态应为一般过去时，即选择A。
第五题A
析：题目翻译：自从少有公立学校能比私人学校优惠，顶尖私立学校的入学竞争就很艰苦了。考点：since用于现在完成时和过去完成时，则排除B和D；而few public schools can compare favorably with private schools是一个事件，一种现状。则选A。
第六题B
析：题目翻译：因为他适合这个公司的职位要求，他应该不久将入职做一名初级职员。考点：As的用法，第一个as用做“因为”；第二个as用作“作为”。根据语义，在办公室上班表现为一般现在是即可，则排除A、C、D。
第七题C
析：题目翻译：18世纪末,这个城市的人口大约二百万。考点：population是不可数名词，作为整体，首先排除B；By the end of：到……时，A跟将来的时间，就用一般将来时，跟现在的时间，就用现在完成时，跟过去的时间，用过去完成时；故选C。

我自己做的，不一定全对。

Answer 2

1 恐怕没有面包了。我们昨天晚上都吃了。不管怎么说，它正在变质。
B.ate, was going 其他选项时态都不对
这道题 判断依据 第一空 有过去时间状语 last night 所以必须用一般过去时 直接排除 ACD
2 A.were already negotiating因为 从句是过去完成时 主句 就不能用现在时 直接排除 BCD
3 B.haven't ever enjoyed 因为从句是现在时 所以 根据意思 主句 用现在完成时

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