用方框中所给单词的适当形式填空，使句子通顺、正确。每词限用一次。

He’s unhappy because of his little dog’s__________ .
This factory was built in the _____________ century.
Welcome to Paris. It is one of the _____________ cities in Europe.
Would you mind_____________the door when you go out?
You’re only twelve years old．Don’t get your ears __________ .