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Dear Mummy,

      How are you? I am fine at school. Tomorrow is National Day. We don't have to go to school. I am going

to take a trip with my friends in the morning. I am going to Zhongshan Park. I am going there by bike. It's near

our school. In the afternoon, I am going to the bookstore and buy some new books. In the evening, I am going

to watch TV. What are you going to do tomorrow? Can you tell me?

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　Your son,

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　Tom

1. What's the date tomorrow?

A. Oct. 1st

B. Nov. 1st

2. Where is Tom going on National Day morning?

A. The bookstore.

B. Zhongshan Park

3. How is Tom going to the park?

A. Ride a bike.

B. On foot

4. Is the park far from Tom's school?

A. Yes, it is.

B. No, it isn't.

5. What is Tom going to do in the bookstore?

A. Buy some new books.

B. Take a trip.

试述高压喷射器201-L的作用？