题目内容：

根据句意及汉语写单词。

1. The physical benefits (好处) of exercise can be ______ (把……分成……) into three factors.

2. She's                (承诺)to do all she can to help．

3.The boy looks much _______________ (生气勃勃的) in the sports clothes and trainers.

4.They are still trying to                  (发现)the cause of the fire．

5.Blue can represent  _______ (悲伤)．When you’re feeling sad，you may say "I'm feeling blue"．