21. When _______ a car, don’t drive at an extreme speed.
A. driving B. driven C. drive D. to drive
22. _______ time, it becomes easier for people under stress to express anger.
A. During B. At C. Over D. In
23. The fireman told us the troubles they had _______ the fire _______.
A. getting, controlled B. got, controlled
C. got, controlled D. getting, to control
