—Could you please _______ the radio, Sam? I can't concentrate on my homework now.
—Sorry, I'll do that right now.
A:turn on
B:turn off
C:turn up
D:turn down
漓江的水真静啊,静得让你感觉不到它在流动;漓江的水真清啊,清得可以看见江底的沙石;漓江的水真绿啊,绿得仿佛那是一块无瑕的翡翠。
下列关于小肠结构与吸收功能相适应的特点的叙述中,不正确的是( )