根据句意，写出括号内所给单词的适当形式。
The dresses ___________（they）are made of cotton, but they sell well because of the famous designer.
These are _________(act) costumes. They are made for these beautiful ladies.
Recently the Forbes magazine conducted a survey to find out who is the _________ (wealth) person in the world.
I once lived in _________ (centre) Chongqing. People like hot food a lot there.