土壤容重的计算公式:open one's fingertip 是什么意思呀？？？

open one's fingertip 是什么意思呀？？？ what's one and one? drop one's course make one's blood he's the one drop one's bag make one's bed pluck at one's bcard 是什么? get to one's feet in one's quest是什么意思