The Wilsons live in ______ A-shaped house near the coast. It is ______ 17th century cottage.
The teacher commanded that the students __________ the classroom before he returned.
Before the tourists set off, they spent much time setting a limit __________ the expenses of the trip.
There is a limit __________ people's life, but no limit __________ the knowledge.
Unfortunately, the research was limited __________ increasing economic profits,__________ protecting the environment.
They are trying to find a new way to __________ the spread of AIDS.