If you don’t wait _______ the red light, you will be punished by the policeman.
| A．at | B．under | C．for | D．on |
Really great people always see the best in others; it is the little man who looks for the worst and finds.
| A．one | B．it | C．that | D．them |
No one knows exactly when our ancestors started talking，but new evidence suggests _______might have happened a long time ago．
| A．which | B．what | C．it | D．they |
—Do you think_____ worthwhile to go all the way to Los Angles to buy that computer?
—Well ,I’m going to visit some relatives, too.
| A．it | B．/ | C．this | D．that |
Though we found _____difficult to avoid economic and financial crisis, we must take measures to reduce its negative impact.
| A．it | B．one | C．that | D．how |
—Does _____please you to give gifts to others?
—Sure．
| A．it | B．that | C．one | D．he |