Withthehelpofhightechnology,mo

With the help of high technology, more and more new substances ______ in the past 10 years.

A．discovered	B．have discovered
C．had been discovered	D．have been discovered

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Ray is a new graduate, and it seems that he has difficulty in dealing with ________ problems arise.

A．whichever

B．whenever

C．whatever

D．wherever

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- These apples look very beautiful.
- They ________. See the price $ 3.99 a pound. Very expensive, aren’t they?

A．should

B．would

C．could

D．might

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- Not really. ________ we started to work in this school.

A．Just after

B．Just when

C．Ever since

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________ with some research materials, he decided on three possible approaches in his experiment.

A．Preparing

B．Prepared

C．Having prepared

D．Prepare

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- Remember the first time we ________, Ed ?
- Of course, I do. You ________ a song on the stage.

A．have met; sang	B．met; were singing
C．met; sang	D．have met; have sung

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