根据所给首字母、单词或中文提示，补全信息。
1.In ancient China，sky lanterns were s________ out to ask for help when people in trouble.
2.The tea produced a pleasant smell after it was ________(boil) in hot water for some time.
3.The Great Wall，the biggest man－made object was ________(build) to protect the country and the people.
4.The tea，one of the most famous drinks, was ________(discover)by accident.
5.Potato chips，the much-loved ________(脆)snack, were invented by mistake.
1.sent 2.boiled 3.built 4.discovered 5.crispy