_______ there are many different types of food, some animals spend their lives eating only one type.
| A．Since | B．Unless |
| C．Once | D．While |
-Do you think you could do without help?
-__________. This is not the first time for me.
| A．Take care |
| B．Hurry up |
| C．Not exactly |
| D．Don't worry |
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 |
__________ at the door before you enter my room, please.
| A．Knock |
| B．Knocking |
| C．Knocked |
| D．To knock |
Before you quit your job，__________ how your family would feel about your decision.
| A．consider |
| B．considering |
| C．to consider |
| D．considered |
Close the door of fear behind you, and you __________ the door of faith open before you.
| A．saw |
| B．have seen |
| C．will see |
| D．are seeing |