Peter:“What made you so delighted at Christmas?”
Mary: “_____________________”
| A．I received many more presents than others |
| B．Because my parents promised me a new car |
| C．My uncle’s coming back from abroad |
| D．As there was an unusual celebration |
My bicycle is nowhere to be found. Who ___ have been using it?
| A．should | B．must | C．could | D．might |
He cut off the electricity immediately he found the dangerous situation, thus ____ a fire accident.
| A．prevented | B．to prevent | C．would prevent | D．preventing |
But at other moments you will find him gentle and weak, _____ he cries about the lost lives of people drowned in ships that have sunk.
| A．as with | B．as for | C．as to | D．as when |
They form a polar molecule, ____ is, ____ with a slightly positive end and a slightly negative end.
| A．which; that | B．it; one | C．that; one | D．one; that |
They find themselves surrounded by colorful rocks, fishes, seashells and plants, all ____ slowly in the blue water.
| A．waving and moving | B．waved and moved |
| C．waved and moving | D．waving and moved |