form the moon, our earth with water .seventy percent of its surface, appears as a blue ball.
| A．seen, covered | B．seeing, covering |
| C．seen, covering | D．seeing, covered |
.
That year his total income, with his reward , 12,000 yuan.
| A．added to; added up to | B．added; added to |
| C．added up to; added | D．adds to; adds up to |
.
----Are you happy with this laboratory?
----Not a little. We can’t have _________.
| A．a worse one | B．a nicer one |
| C．such a worse one | D．such a nicer one |
.
Some companies have introduced flexible working time with less emphasis on pressure ____.
| A．than more on efficiency | B．and more efficiency |
| C．and more on efficiency | D．than efficiency |
.
From Mum’s love, patience and understanding, I have learned what a huge responsibility ___ is to raise a child.
| A．it | B．that | C．this | D．one |
.
–Who has broken the window in my room?
--Who else ___ it but your naughty son!
| A．could do | B．could have done | C．might do | D．must have done |