用所给单词的适当形式完成句子。

1.He learned it_____ (he).

2.Lesson 3 is not so_____ (playful) as Lesson 5.

3.You should send for the doctor as_____(faster) as possible.

4.The more you learn, the_____(great) knowledge you will get.

5.How heavily it rained yesterday! But today it is even_____ (heavy).