我在预习
用ever,already,just,nerver,yet,befor等词填空
1.--Have you _____ been to the space station?
--No,I haven't _____been there.
2.--Have you done your homework ______
--Yes,Ihave.I've _____ done it.
3.I've been in China for two years ______ .
4.My brother has ______ seen an interesting place _______ .
5.His parents have ______ gone to Pairs,so he is at home alone.