根据提示，完成单词。
What's the ________(sth．which makes your voice much louder)made of?
Do you know where the ________(the way out of a room or a building)is in this theatre?
The ________(the people who come to watch a show)in the theatre were very excited when they saw their favourite singers．
Do you know that ________(a person who performs in a show)in white?
Jay Chou is dancing on the ________(an area where actors, dancers, singers, etc．perform)．
用适当的介词填空。
Rice must be harvested ________ the right time．
He was working ________ the Maths problem when the light went out．
He was to be a host ________ a charity show．
We had a lot of support ________ local business．
________ meals, you should wash your hands．