tier
n
any of a series of rows (esp of seats) or parts of a structure placed one above the other 一排(尤指座位); (阶梯式的)一层
a box in the first tier, ie in atheatre (剧院中的)第一排的一个包厢
a wedding-cakewith three tiers/a three-tier wedding-cake 有三层的结婚蛋糕. =>illus at layer 见 layer 插图.
We set off down the hill. At first it was easy walking over the grass. Then the grass turned to bushes and the hillside became steeper. We climbed over rocks, through trees and found it more and more difficult to get down the hill. By now we were beginnin