Such a problem is＿＿＿＿difficult for a primary school student ＿＿＿.
| A．so； to work | B．very too； to work out |
| C．rather too； to work out | D．quite too； to answer |
Mary would rather_______ inside_______ while I would rather she________
to go shopping with her friends.
| A．stay; reading; went | B．stay; reading; goes |
| C．stayed; to read; goes | D．stayed; reading; would |
He advised farmers to choose the best seed-heads ,__________ that had the best color .
| A．不填 | B．ones | C．this | D．the ones |
Great changes have taken place in that factory. It is no longer _________
it was 20 years ago,_____ it was so poorly equipped.
| A．what ,when | B．that ,which | C．what ,which | D．which ,that |
When first __________to the market ,these products enjoyed great success .
| A．introducing | B．introduced | C．to introduce | D．being introduced |
__ It is so late. Our son __________ be back .
__ Don’t worry . I dare say he ________ have some extra work to do.
| A．can ; must | B．will ; might | C．should ; must | D．must ; may |