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Now boys and girls，let’s begin our class．As I know, you are interested in some strange math problems．So today I’m going to tell you one of the strangest ways to multiply numbers of two or more figures．Maybe you don’t know the word “multiply”．The word “multiply” mean s“乘．．．，乘法的乘”in Chinese．For example，8 multiplied by 2 is l6．It means “8乘以2是16” in Chinese．Do you understand now? Of course．there are many ways to multiply numbers．But here is one of the strangest．

Imagine you wish to multiply 23 by 17．In Chinese，it means 23乘以17．Half of 23 is 11．5．Write only 11 under 23 as you see in the paper．Half of 11 is 5．5．Write only 5 under 11．Now think it over, what number will you write under 5? Yes, you are right, just 2．Now please write the number under 5．Continue until you have 1．

Now write numbers under 17．But this time you must multiply each number by two to write the number under it．For example, you should write 34 under 17．As a rule, what number will you write under 34? Yes, you are right, 68．Now please write the number under 34．Continue until you have a number on the same line as 1．Now draw a line through any row that has an even number on the left．Yes, even number means 偶數(shù) in Chinese．In our example there is only one even number．Right? Now please draw a line through the line that has au even number on the left．Now add the rest of the numbers in the right hand row．Believe it or not, you will get the right answer．What is it? OK．Please write the number, I mean the right answer in the right place．

Now class, I'll give you several minutes to discuss how it works．

1．What is the speaker most probably doing now?

A．Giving a lesson．                        B．Holding a meeting．

C．Having a party．                         D．Playing a game．

2．What number does the speaker tell you to write under 5?

A．2．                B．5．5．            C．11．              D．10．

3．What is the last number you should write?

A．68．            B．272．             C．391．             D．255．

4．Which subject is the speaker teaching?

A．Chinese．          B．Chemistry．        C．Math．            D．Science．

5．What does the speaker tell you to do at the end of the talk?

A．To have a rest．                         B．To do homework．

C．To have a discussion．                    D．To play a game．