—Which do you prefer,a CD player or a Walkman?—________.I prefer a portable computer.
_____________ is necessary __________ he trains himself before the Guangzhou Marathon.
___________ a sportsman is a hard job, but you are very excited if you are successful in ____________a good medal.
---Which do you like ___________ , apples or pears? --- I like pears.
I always go to sleep ___________ the light on.
He finds watching movies ______because the people speak too quickly.