A:①②③④组成的胚由胚珠发育而来
B:D花中最重要的结构是花瓣
C:种子萌发时首先突破种皮的是②胚芽
D:E果实由种子和果皮组成
⑴You need a swimming cap. ____
⑵First,you should wash yourself. ____
⑶Next,you should do warm-up exercises. ____
⑷Then, you can enjoy your swimming lessons. ____
⑸You need a swimsuit.____
A. B. C. D. E.