Grand Slam winner Li Na has made up her mind that she _____ from tennis because of her knee injuries this October.
—— Would you mind if I asked you where you’re from? —— _______________.
Historically, ________ main material for making tables has been wood, but ________ metal and stone have also been used.
__________ has recently been done to provide more buses for the people, a shortage of public vehicle remains a serious problem.
Because Sarah has always saved __________, she is now able to afford a big house.
According to one theory, taking part in high-culture activities makes __________ easy for teenagers to make friends with powerful older people, __________ thus increases the chances of their lives turning out well.