. Several weeks had gone by ________ I realized the painting was missing.
| A．as | B．before | C．since | D．when |
Find ways to praise your children often, ____ you’ll find they will open their hearts to you.
| A．till | B．or | C．and | D．but |
—You can have a pet dog, but suppose you get bored with it in a few days? _____？
—We won’t, we promise!
| A．Then what | B．All right | C．How come | D．So what |
As the story______, the truth about the strange figure is slowly discovered.
| A．begins | B．happens | C．ends | D．develops |
Did you predict that many students ______ up for the dance competition?
| A．would sign | B．signed | C．have signed | D．had signed |
In the last few years thousands of films __________ all over the world.
| A．have produced | B．have been produced |
| C．are producing | D．are being produced |