Dear Zhang Peng,

    I have a new school. It's big and beautiful. There are many trees and beautiful flowers in it. The school buildings are yellow and white. We have a music room, an art room, a computer room and a library. I'm in Classroom 1. It's on the first floor. It's next to the library. I like our playground very much. It's so big , we often play football there.

    Welcome to my school!

Yours,

John

种子萌发所需的外界条件是（　　）

①适量的水分  ②充足的光照  ③适宜的温度  ④丰富的养料  ⑤充足的空气．