A:胰岛素能调节糖代谢
B:干扰素是一种广谱抗病毒物质
C:载体能转运物质
D:生长素促进植物生长
—How about joining us in the summer camp?—I wish I could, ___________ I have to practice for the piano test.
28颗星星,每9颗可以穿成一串,可以穿成几串?还剩几颗?
He is a much better (好得多) tennis player (运动员) than(比)me. When we play, he always wins(获胜)____________.