We may find that learning a foreign language does not have to be________learning our mother tongue,but can in fact be twice ________.
Burning all the lights in the classroom will be a great______ on electric power.
The environmentalists said wild tiger’s______ on the Thai mountain was a good indication of the better environment.
Although I had read the book assigned by the professor several times, it didn’t make any______ to me.
If you build a house with good_______ , it will last long.
A(n)______ is a person who understand people’s characters.