I own over a thousand books为什么要加a,不加可以吗?

I own over a thousand books 和 I have over a thousand books的区别为什么不用I have over a thousand books I own over a thousand books为什么要加a,不加可以吗? I own over a thousand books,they cover every inch of floor space帮忙造个句I own over a thousand books,they cover every inch of floor space这句话如果用because .which 造句,怎么造句 This has not been easy because i own over a thousand books.这句话中been是什么用法 This has not been easy because I own over a thousand books.请问这个完整的句子叫什么句子 because ,引导的叫什么句子 That's over.I lost my own,I found myself coming back I want a life of my own I have a quality of its own i look forward to__(own) a computer. I hope _____(own)a computer I have a new bike ____of my own on my own of one's own in my own 20.I was driving along,______my own business,_____the police signalled to me to pull over.20.I was driving along,______my own business,_____the police signalled to me to pull over.A. minding which B .minded; when C. minding;when D. 请问此题为什么选A,选D应该也可以啊,-How many students are there in your school?-____t请问此题为什么选A，选D应该也可以啊，-How many students are there in your school?-____the students in our school _____ over two thousan It is certain that he will__his buiness to his own son when he gets old.A take over B think over C hand over D go over There are （ ） trees on the hill.A.thousands of B.two thousand of C.two thousands D.thousan of I'll bring ____ dictionary with me.A.myself B.ourselves C.my own D.own I cried a river over you. Then he smiled and told me I would receive an extra thousand pounds a year!出自新概念中,请问（1）a year 表示就是今年一年,还是每年呢,那么每年不是应该用every year吗,（2）另外句子中已经有具体的数字 thousan