句型转换（共10个空，每空0.5分，满分5分）
小题1: Going to sleep early is important for the teenagers.
__________ _________ _________ for the teenagers to go to sleep early.
小题2: You should read more English books.
You ________ _________ read more English books.
小题3:He had to stay up late last night because he hadn’t recited NCE.(改为否定句)
He ________ _________ _________ stay up late last night because he had recited NCE.
小题4: If it doesn’t rain tomorrow, we will climb Baiyun Hills.
We will climb Baiyun Hills _________ it _________ tomorrow.