i have a bag with books in it为什么in it 不能省略,i have a bag with books 这样不对吗

I have a bag. i have a bag with books in it为什么in it 不能省略,i have a bag with books 这样不对吗 I have a bag with books in it .这里的in it 做什么成分?RT I have a bag.一般疑问句能变成：Have I a bag? I have a bag.改为否定:I have not a bag.I don't have a bag.哪个对?Have的否定变化. i _____ a bag with me and i am putting the rubbish into the bag. I have a bag in blue.I like it a (l ).I go to school with it every day.填空并翻译 look i have a new bag.my bag is newest than your bag.( ) abaut mary's bag.her bag ( ) the ( )of all. She played with you,you take my bag.I grass your mama of,you think you have a lot of clout?I told you.I hat I have a computer game in my bag (一般疑问句) M什么 I have a look at your new bag? I don't have a bag.改为肯定句是什么 I,a,cap,have,in ,bag ,my.连词成句 为什么说I have a bag 却不能说I am have a bag同志们,谢啦 I have a bag with books in it.(“in it” 不能省略)?书上说in it 不能省略?为什么?in it 是修饰book的吗?with books in it 应该是修饰bag的定语吧?不太懂! Mike() a nice bag and I() a big school bag.A.does:is B.is;have C.has;have i have got one hundred Yuan.i went tobuy a school bag. i a____ have a school bag so i do not need another any more