We offered these students a summer course , aimed _____ improving their spoken English.
The driver can adjust the heating in winter and the air conditioning in summer to suit his own _____.
She felt _____ of having asked such a silly question when the audience couldn't help laughing.
After a short holiday, he _____ himself once more to his studies.
The family is a cooperative enterprise for which it is difficult to _____ rules, because each family needs to work out its own ways to deal with its own problems.