he is going to visit to her aunt sa soon as he will arrive in beijing ,为什么要将其中的will arrive改成will arrives,请问,在这句话里有什么区别吗?

he is going to visit the museum this saturday?is going to visit the museum 提问 He is going to visit the museum this saturday.对 is going to visit the museum提问 He is going to visit the college _____ he studied 30 years ago. He told me that he_____the park the next day.a.will visit b.is going to visit He is going to visit an artist tomorrow.(visit an artist是画线部分,对画线部分提问 He _______ the Museum of Chinese History tomorrow.A is going to visit B visit C visits He _______ the Museum of Chinese History tomorrow.A is going to visit B visit C visits Amy is going to visit her Amy is going to visit her uncle He is going to visit his grandparents.（变成一般疑问句） Is Sam going to visit his grandparents next Sunday?no,he ________ (isn't,doesn't) He is going to visit his friends in Shanghai.改为一般疑问句并作肯定回答 He is going to()the science museum tommorrow.用visit的恰当形式填空 把He is going to visit Australia with his parents改为否定句 如何把He is going to visit his teacher next week改为否定句 he is going to ________ his teacher a post carda.buy b.visit c.turn He is going to visit his uncle nest saturday（改为同义句) He is going to visit America next month.(用in1999改写)