根据句意，用所给单词、短语的适当形式填空，每词或短语只限使用一次。

little    one    child     fly    give up

You are an excellent boy. Never _______________ trying easily.
The football belongs to these _______________. Give it to them.
Brian usually _______________ to Canada because he thinks it’s very fast.
This is my _______________ time to visit London and I’m very excited.
The more plants there are, the _______________ pollution there will be.