A:生殖和发育的特征
B:生长现象的特征
C:遗传和变异的特征
D:新陈代谢的特征
— They are eager for a great victory.
一 Work hard and I believe they‘’ll surely make it.
将△ABC的∠C折叠,使C点在AC边上,折痕为DE,则( )