When you are preparing for your college adventures abroad, it is easy to ______.

A．How to make quotations.
B．Whether he should quote opinions.
C．How many quotations to use.
D．Whether quotations are really necessary.

A．She didn’t make full preparations for her lessons.
B．She was blamed by the professor for her carelessness.
C．She lost her key and couldn’t enter her house.
D．She was afraid of the professor.