Some experts think reading is the fundamental skill upon______school education depends.
A. it B. that C. whose D. which
_____ the difference between the two research findings will be one of the worst mistakes you make.
A. Ignore B. Ignoring
C. Ignored D. Having ignored
I’m so ______ to all those volunteers because they helped my terrible day end happily.
A. special B. superior C. grateful D. attractive
A ship in harbor is safe, but that’s not ______ ships are built for.
A. what B. whom C. why D. when
Just as I got to the school gate, I realised I ______ my bank in the cafe.
A. have left B. had left
C. would leave D. was leaving
______ scientists have learned a lot about the universe, there is much we still don't know.
A. Once B. Since C. Though D. Unless
