2) 缺少的意思是缺少必需的mean to be without something essential or greatly desired.首字母LWNR想成左右为难<==缺少 (essential本质的必不可少的implies what belongs to the nature of a thing and cannot be removed without destroying the thing,如conflict is an essential element in drama矛盾是戏剧不可缺少的元素)