表达 vs. 表现 vs. 表示 vs. 显示
表达, to express
他表达了他的爱意。to express something, used for expressions
表现, verb: to show, to perform. noun: behavior
verb 他表现出了他的才华。he has shown his talents.
noun 他的表现不是很好。 his behavior is not very good.
表示 means ...
这表示他喜欢你。this means that he likes you.
显示 to display or show.
手机能显示图片。phones can display/show pictures.
hope this helps.