a drop in the ocean沧海一粟
within a stones throw一箭之遥
ki11 two birds with one stone一箭双雕
A fall into the pit, a gain in your wit..吃一堑，长一智。
at sixes and sevens乱七八糟
on second thoughts再三考虑
by ones and twos两两地，零零落落地
Two heads are better than one.三个臭皮匠胜过诸葛亮。
Can you come down a little? --Sorry, its one price for all.
He had one over the eight after be drank only half bottle ofthewine。
One mans meat is another mans poison.人各有所好。
Ill love you three score and ten.我会一辈子爱你的。
Ten to one he has forgotten it.很可能他已经忘了。
His mark in math is second to none in the class.