______ more and more trees cut down, many animals and insects are dying out.
| A．Because | B．With | C．As | D．Since |
_________ with the size of the whole earth, the biggest ocean does not seem big at all.
| A．compare | B．when comparing |
| C．comparing | D．when compared |
I recognized him_________ I saw him in the crowd.
| A．now that | B．in case | C．the moment | D．if |
—Li Ming went abroad in 2000.
—No wonder. I ______ him ever since.
| A．don’t see | B．hadn’t seen | C．didn’t see | D．haven’t seen |
______ difficult the problem was, he tried his best to solve it.
| A．No matter | B．Although | C．Whatever | D．However |
It is the teacher _____taught me when I was a child _____ I’m going to visit.
| A．that, which | B．who, that | C．who, which | D．whom, that |