It was with great joy _______ Tom received the news that his lost son had been found．
| A．because | B．which |
| C．since | D．that |
Extra warmth from sunlight can put an additional ________on the air-conditioning system.
| A．weight |
| B．anxiety |
| C．load |
| D．tiredness |
Earth Day is celebration of life and our planet. It is a reminder that we need to________the world we live in and that we should learn to respect life and nature.
| A．care about |
| B．think of |
| C．refer to |
| D．watch out |
There isn't much money left. We must ________our spending.
| A．increase |
| B．prevent |
| C．rise |
| D．limit |
I ________back the money.
| A．rely on him to pay |
| B．rely on his paying |
| C．depend on him to pay |
| D．all the above |
He hurried to the booking office, only________that all the tickets had been sold out.
| A．to tell |
| B．to be told |
| C．telling |
| D．told |