His illness ________ his absence.
| A．leads for | B．accounts for |
| C．provides for | D．pays for |
_______ the satisfaction of our customers, the products worked very well.
| A．With | B．For | C．At | D．To |
She gave me the suggestion that I try to ________ some money every month for special use.
| A．set back | B．set off | C．set down | D．set aside |
Whenever we are in ____ trouble, we should never lose______heart.
| A．a; the | B．a; a | C．/; / | D．/; the |
--- I think the waiter has forgotten us. We ________ here for over half an hour!
--- I think you’re right. He probably thinks we have already ordered.
| A．are waiting | B．have been waiting |
| C．have waited | D．will wait |
. When she woke up, she realized that things she had dreamed about could not _______ have happened.
| A．possibly | B．exactly | C．certainly | D．usually |