在光学显微镜下观察洋葱鳞片叶表皮细胞时，不容易看到的结构是 。
细胞膜
—Can you _________ us ________ your new house?
—OK. It's big and nice. [ ]
A. tell, with
B. tell, about
C. say, about
D. talk, about
肾门向肾内延续于一个较大的腔称为()
A．肾大盏
B．肾盂
C．肾蒂
D．肾门
E．肾窦
