用present perfect tense ,simple past tense ,

present perfect 用present perfect tense ,simple past tense , present perfect simple and present perfect continuous Present simple,present continuous,present perfect simple,present perfect continuous present perfect continous是什么 present perfect是什么意思 The present perfect tense 什么时候该用 present perfect 什么时候该用past simple? present perfect tense,past perfect tense两者的用法,用中文答 什么是PRESENT PERFECT CONTINUOUS啊? _____he____(finish) his work today?Not yet用什么时态present perfect tense? present perfect 现在完成时?如果是 又用那些单词 句型是什么give me example 请用英语五种句子结构：SV,SVC,SVO,SVOC,SVoO 和八种时态：1 simple present,2 present perfect,3 present progressive,4 present perfect progressive,5 simple past,6 past perfect,7 past progressive,8 past perfect progressive造句 就是说 write the sentence in the present perfect 求 4 个 present perfect progressive 句子 求 4 个 present perfect progressive 句子.. the present perfect tense的中文 present perfect continuous和present perfect simple的区别与用法