Nowadays people are more concerned about the environment ___ they live.
Only when your identity has been checked ________.
From the ________ look on my teacher’s face, I know she was _______ with the results.
The UK ________ Great Britain and Northern Ireland, is a country famous _____ its history.
He felt that he _______ the coldness that had grown between them.
You’d better not _______ these two sentences, otherwise thereaders cannot fully understand you.