concentrate on作状语时,是用concentrating on还是concentrated on ?

concentrate on作状语时,是用concentrating on还是concentrated on ? CONCENTRATE ON有无现在进行时 concentrate on有无现在进行时 Our teachers believe that if we did that,we would concentrate more on our studies这个句子是if引导的条件状语从句,为什么还用过去式 concentrate on等于 concentrate on的用法 i concentrate on concentrate on 和 foucus on 区别形容集中注意力的是 foucus on focus on concentrate more on 与concentrate much on 都可以吗 concentrate on you的意思 concentrate on 和 concentrate to 有什么区别 concentrate造句 注意,不是concentrate on要初三水平 concentrate on 与focuse on 的区别 centre on 和 concentrate on比较 concentrate concentrate concentrate 在Concentrate with all your intelligence,all you enthusiasm,on doing today's work这个句子中concentrate是不及物动词?如果用作及物动词,写成：Concentrate all your intelligence,all you enthusiasm,on doing today's work应该也对吧