—Some English idioms are difficult to understand.—Exactly, ________ you know the meaning of each word.
It's no such ____ long distance from here to ____ supermarket. We can walk there.
The quality of the teachers will influence the students,and ________, the quality of the students will influence the teachers.
That was the last time I saw my father before he _____.
The experiment __ to be .
Many _______ of years later, the first extremely small plants began to appear on the surface of the water.