.Ihadbeenpuzzledovertheproblem

.I had been puzzled over the problem for over an hour without any result, _____ all at once thesolution flashed across my mind.

A．while

B．when 　　

C．then 　　

D．as

登录免费查看答案和解析

相关试题

Exciting as its special effects are ______, there is too much violence in the film.

A．being watched

B．to be watched

C．watching

D．to watch

收藏答案/解析

According to the rules, students ______ get grades not lower than 85% in any subject in order to get the scholarship.

A．will

B．shall

C．may

D．would

收藏答案/解析

Student loan is supposed to provide financial support for people who would ______ not be able to go to college.

A．otherwise

B．meanwhile

C．therefore

D．nevertheless

收藏答案/解析

The young scientist has made such great achievements in his chosen field ______ nobody else can make.

A．that

B．what

C．which

D．as

收藏答案/解析

We were told not to touch the equipment in the laboratory unless ________.

A．allowed to do

B．allowing to do

C．allowed to

D．allowing to

收藏答案/解析

推荐套卷

热门套卷