________hard before, Tom is afraid of failing in the exam.
| A．Having been worked | B．Not to have worked |
| C．Having never worked | D．Never have worked |
After retirement, learning a musical instrument may be harder than ______ when you were a kid.
| A．it may | B．it was | C．it does | D．it did |
We cannot figure out ______ quite a number of students were infected with the flu.
| A．that | B．when | C．why | D．where |
I ______ of your trying to earn some money, but please don’t ignore your studies.
| A．permit | B．agreed | C．promise | D．approve |
The boss ______Mary to finish her job within a week.
| A．suggested | B．insisted | C．demanded | D．required |
Maggie is a neat and tidy student, who likes to have everything ______.
| A．in public | B．in place | C．in return | D．in practice |