根据句意和汉语提示，填写恰当的短语完成下列句子。 1. _____ (首先),
题型：翻译题
问题：
根据句意和汉语提示，填写恰当的短语完成下列句子。
1. _____ (首先), the computer room must be kept clean.
2. _____ (有时) he goes to the English club after school.
3. Too much work and too little rest can _____ (引发) illnesses.
4. I am happy that I bought the computer _____ (以最低的价格).
5. This book is specially _____(针对) teenagers.