Rita _________two hours every Sunday afternoon to spend with her son.
Who________ for the pollution of our earth?
— So hard ______ in the past few months that he has made great progress in English. — I can see that; only a few mistakes ______ in the exam.
Seeing their son playing computer games all day, the parents don’t know ______ it.
——Whose advice do you think I should take? ——_________________________.
The Big Ben, _______ we visited during a recent trip to Britain, is one of London’s tourist attractions.