Itwasnotuntil1911,thefirstvita

It was not until 1911, _______ the first vitamin was identified, _______ people realized the importance of it．

A．when; which

B．when; that

C．that; which

D．that; that

登录免费查看答案和解析

相关试题

—I’m thinking of the test tomorrow. I’m afraid I can’t pass this time.
— ! I’m sure you’ll make it!

A．Go ahead	B．Good luck
C．No problem	D．Cheer up

收藏答案/解析

It was only after he had read the papers Mr. Gross realized the task before him was difficult to complete.

A．when

B．that

C．which

D．what

收藏答案/解析

—Did you enjoy yourself last night?
—Yes, it’s very nice of you. I appreciated to your birthday party.

A．to be invited	B．to have invited
C．having invited	D．being invited

收藏答案/解析

Believe it or not, Lucy’s sister suddenly tears when we were eating.

A．burst out	B．burst in
C．burst into	D．burst on

收藏答案/解析

basic fist-aid techniques will help you respond quickly to emergencies.

A．Known	B．Having known
C．Knowing	D．Being known

收藏答案/解析