小医生，下列各句均有一处错误， 请找出并改正。

1.She is going to go some shopping.

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2.What time does Jim usually gets to school?

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3.Twenty minutes later, the old man arrives the hospital.

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4.Sorry, can you show me the way to the museum?

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5.It begins rain when he leaves.

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简述大额支付系统与小额支付系统的关系。