(), you need to give all you have and try your best.

单项选择题Gun control is a subject () Americans have argued for a long time.

A．of which
B．with which
C．about which
D．into which

单项选择题So sudden () that the enemy had no time to escape.

A．did the attack
B．the attack did
C．was the attack
D．the attack was

单项选择题Critics believe that the control of television by mass advertising has () the quality of the programs.

A．affected
B．effected
C．lessened
D．declined

单项选择题A workaholic works too much and usually forgets to have meals and go to bed. (), he doesn't have good health.

A．As a matter of fact
B．As a whole
C．As a result
D．As a rule

单项选择题In the Mediterranean seaweed is so abundant and so easily harvested that it is never () of great.

A．fare
B．payment
C．worth
D．expense