区别：1.词义不同；2.词性不同.
sooner ['su:nə] n.抢先占地的人
adv（副词）.比预期早
词组扩充：sooner or later 迟早,早晚
例句：It is regrettable that the police were not informed sooner.遗憾的是没有早些报警.
soon [su:n] adv.（副词）不久,很快,早
例句：The whole building was soon ablaze.整栋大楼很快就熊熊燃烧起来.
soon和sooner的用法及其区别