位于地势的第二级阶梯,具有地势平坦,一望无际的高原是[ ]
A.青藏高原
B.内蒙古高原
C.黄土高原
D.云贵高原
答案:B
Daniel's grandmother is very old. She can't _____ him well.[ ]
A. listen
B. listen to
C. hear
D. hear to
铺底料的作用是什么?