精选优质文档-倾情为你奉上一、單項選擇。 1、Both his parents look sad . Maybe they _whats happened to him . knew have known .must know .will know 2、He has _ been to Shanghai , has he ? already .never .ever . still 3、Have you met Mr Li _？ .just ago .before a moment ago 4、The famous writer _ one new book in the past two year . . is writing .was writing .wrote .has written 5
