在下列各句的空白处填入一个最恰当的单词，使句子意思完整，语法正确。
1. Don't tell lies. Please tell the________.
2. I have already had a toothbrush, and also I need a tube of________.
3. These colorful books are________at little kids.
4. Please make a________of three sports you like, and three sports you don't like.
5. "Whiter than white"is a________for a kind of soap.
