37.After _______ the area for three hours, the police found the truck near a river.
| A．searching | B．searching for |
| C．in search for | D．looking for |
—Where did you pick up the stamp?
—It was at the post office ________ we worked in the summer vacation.
| A．that | B．where |
| C．which | D．when |
Who ________ that played a trick on the new English teacher?
| A．it was | B．was it |
| C．he was | D．was him |
Where do you think ________ we can buy that bestseller?
| A．it is that | B．is it that |
| C．that | D．it |
There is no doubt that eating organic food will make you healthier, ________？
| A．will it | B．does it |
| C．is there | D．is it |
It was today's activity ________ let me know the importance of teamwork.
| A．where | B．which |
| C．that | D．what |