1 He began to write poems in his thirties.
问题描述:
1 He began to write poems in his thirties.
问:最后为什么用thirties而不用thirty?
2 When he moved to England in the fifties,he was already in his forties.
问:为什么fifty和forty都用复数?
3 A nucleus is about one millionth the size of an atom.
问:为什么用millionth而不用million?
答
12题的用法是短语 in one's thirties/fifties...数字复数,这个是表示在某人多少岁时,例如,在他三十几岁时,但没说明确切是几岁,只是31-39里边的一个数字而已.3的意思是 核子大约是原子的百万分之一.这里表示分数的.m...