A:在胸腺中发育成熟的T淋巴细胞可参与细胞免疫
B:效应T淋巴细胞可攻击被病原体感染的宿主细胞
C:T细胞释放的淋巴因子不能促进受到抗原刺激的B细胞增殖
D:T淋巴细胞和B淋巴细胞都是由造血干细胞发育成的
看图片,选句子
A. Whose storybooks are these?
B. John is jumping.
C. Who is singing?
D. Look !Zoom is eating watermelon.
E. It is drinking water.
____
Amy was reading a book __________I came in.