用方框中所给单词的适当形式填空。每词限用一次。

The tea _______ a pleasant smell and it’s popular with quite a lot of Chinese people.
I used to sing__________, so I was afraid of singing in front of the whole class.
You shouldn’t eat too much ___________ food. It is bad for your teeth.
It’s difficult to _________the job alone, so we should work together and help each other.
Jack, a kind and ____________ boy, is always ready to help others.