_____ his ability of speech, he has made use of each chance.
| A．To improve | B．Improving | C．Being improved | D．Improved |
The old man turned his business over to his younger son, ________made his elder son discouraged.
| A．who | B．what |
| C．that | D．which |
Stand _____ you are, and I will come and help you.
| A．while | B．where |
| C．which | D．what |
Keep away from the dog , _______it will bite you.
| A．and | B．so |
| C．or | D．but |
He made up his mind to devote all he could _____ his spoken English before going to college.
| A．to be practicing | B．practicing |
| C．practice | D．to practicing |
We live in a society ______ there is a great deal of debate about competition.
| A．where | B．which |
| C．when | D．that |