these days students in some schools are asked not to use mobile phones这个的主语是什么?难道不是学生吗?为什么这句话是被动语态.（我还没学）.我看到被动语态句子的结构 一般动词在人称的前面 还有个by.

These days ,many students These problems are very c____ to students these days These days many students like to make friends on line. ________ dictionaries are very popular with students these days. Many students can enjoy f() lunch at school these days. students these days often have a lot of worries.求课后题：2c 2d These days it is found that school students hardly have any sports.(翻译成中文） the coming final exam makes all the students ______(feel)busily these days all of the students are （）（）（） a math test these days. these days school students haydly have any sports的中文意思 These days students have too many homework to do every day.哪错? have you ever had a school party?these days the students the coming final exam makes all the students ______(review）busily these days 连词成句 the,these,students,preparing,days,coming,are,for,meet,the,sports. these days 是什么时态? These days more than These Days 歌词 Days Like These 歌词