improve on sth.为什么要用on

improve on sth.为什么要用on improve in和improve on的区别 ’improve’与 ’improve on ’有何区别 improve in与improve on的区别 impress sth.on sth. 有decide doing sth.吗?为什么书上写decide on(upon) sth./doing sth.? Dale,improve,write,pen,pals用by doing sth 的结构改写成句 子 advice on/about sth.什么时候用advice on sth.什么时候用advice about sth.请讲解 Regular review leads to improved performance on tests.为什么to后面用了名词improved而不用动词improveimproved是名词改善改进的意思,improve是动词改善改进的意思.to后面不是要跟动词嘛? 用FIX STH ON SB造句! 用 spend …on sth造句 用keep on doing sth 造句 用congratulations to sb.on sth.造句 用plan on doing sth造句 put sth on sth造句 英语省略用法spending on sth.than on sth.中后面的on可以忽略吗,为什么 have sth to be done/have sth done?为什么要用have anyting to be done? plan on doing sth 该语法正确吗?为什么?