色散媒质
参考答案：
使在其中传播的电磁波出现色散的煤质。
—Would you like to climb mountains with me this Sunday?
—I’d love to. But I _______ play table tennis against Class Three.
A．am going
B．am going to
C．am
D．going to
软兜鳝鱼选用的鳝鱼部位是______。
A．鳝鱼的脊背肉
B．鳝鱼的尾部肉
C．鳝鱼的腹部肉
D．鳝鱼腹背相连的肉
