根据句子意思及所给的词首字母或汉语提示，完成下列单词。
Both of them are nice and cheap. I really don’t know which one I should c              .
F          the doctor’s advice, and you will get better soon.
Our Chinese teacher wants us to write a d          every day to improve our writing.
That baby has only three           (牙齿) . He can’t eat that apple.
Tan Jiexi’s song “Run, Run, Run” is very           (流行的) among young people.