The boy has a pen.(改为否定句） 为什么是does not have,而不是hasn't?

she has a pen pal in the USA改复数 the girl has a pen 改否定句 The boy has a pen.(改为否定句） 为什么是does not have,而不是hasn't? HE HAS A NEW PEN.改为否定句怎么改? He has a new pen.(改一般疑问句） KangKang has a pen pal怎么改一般疑问句 The boy in the classroom needs a pen of yours中的a pen The little boy needs a blue pen 里的表语? Is ___your pen friend?A.a boy B.a girl C.the boy D.a friend the boy have a headache.改病句 This is a pen. The pen is a red 怎么改正确在线等 Each of the students ________( have, has) a pen pal. The following ,which is right?A.my pen has lost.B.My pen is lost Tom has a new pen怎么改一般疑问句和否定句? The boy (writes/to write)the letter needs a pen.为什么用to write The boy in the classroom needs a pen of yours的定语是什么? The boy in the classroom needs a pen of yours中的词法与句法 Has he got a pen