1 existing or happening in some places but not others 散落零碎的；局部的: patchy fog/clouds/rain 部份地区出现的雾╱云╱雨

2 not complete; good in some parts but not in others 不一致的；不完整的；零碎的；一鳞半爪的: My knowledge of German is rather patchy. 我对德语一知半解。