Complete the sentences with the given words in their proper forms (用括号中所给单词的适当形式完成下列句子。每空格限填一词)
1.We should have enough exercise to stay________. (health)   
2.He watches television________a day. (one)   
3.How many outdoor________do you like? (activity)   
4.You should eat________(little) meat and________(many)vegetables and fruit.   
5.Ben is________interested in cartoon films. (real)