(1) since句型：主句用完成时例：My aunt has worked in a clinic since (2) since when +完成时例：Since when have you planted so many young trees?从什么时候你种植了这么多小树的?(3) This/it is the first () time sb have/has done sthThis/it was the first () time sb had done sth例：This is the first time I have been 这是我第一次到这儿。(4) by…(到……为止)到过去某个时候为止用过去完成时，到现在为止用现在完成时，到将来某个时候为止用将来完成时。例：She will have finished the book by my next 到我下一个生日为止，我将完成那本书。(5) in the past time( two days/) +完成时例：In the past 10 years， there have been great changes in our family 在过去的十年里，我们的家庭生活发生了很大的变化。(6) hardly (no sooner than)句型用过去完成时例：Hardly had I reached the school when the bell 我一到学校，铃子就响了。No sooner had we sat down at the table than the phone 我们刚坐到桌子旁边电话就响了。(7) 未实现的愿望打算等等用过去完成时例：I had thought I could pass the final examination but I
英语作文开头万能句：1、 An idle youth，a needy 少壮不努力，老大徒伤悲。2、 I＇m sorry I took so long to 很报歉给你回信晚了。3、guarantee the stability and prosperity of our 保障社会的稳定和繁荣。4、 Make yourself a better person and know who you are before you try and know someone else and expect them to know 在你想了解别人也想让别人了解你之前，先完善并了解自己。5、 the recent research has shown 最近研究表明。6、 I hope everything is all 我希望（你）一切都好。7、 Nothing for 不费力气，一无所得。8、Standing firm is to challenge difficult courageously and to leave the smile after sccess to 坚强，就是勇敢的向困难挑战，把成功的微笑留给自己。9、 The future is scary but you can＇t just run to the past cause it＇s 未来会让人心生畏惧，但是我们却不能因为习惯了过去，就逃回过去。10、 What today will be like is up to me，I get to choose what kind of day I will 今天什么样，完全由我决定，今天怎样度过，由我选择。
