necessity基本解释
n,需要；[数]必然性；[经]必需品,同近
She saw books as a necessity, not a luxury..她视书籍为必需品而非奢侈品。
需要；必然性；必需品英释nnsomething that you need to have in order to live
of necessity,必然地；不可避免地.短语
