Do you often help your father ___ the farm work during the summer vacation?
| A．for | B．on | C．in | D．with |
He met Rachel at her college graduation ceremony in 2011, ________ he was later to marry.
| A．which | B．when |
| C．where | D．whom |
—When did you get home last night?
—It was almost midnight ________ we arrived home.
| A．that | B．before |
| C．since | D．when |
________ is known to all is that effective measures should be taken to deal with the problem of the overexploitation of our resources.
| A．What | B．It |
| C．As | D．Which |
I think you should work harder ________ you are satisfied with the way things are.
| A．if | B．when |
| C．since | D．unless |
．Ram explained to his mother ________ he would get home late that night because of extra work.
| A．that | B．which |
| C．what | D．whether |