数词加减乘除的表示法
1. 加”用plus，and或add表示;等于”用is，make，equal等词表示。
2+3=? 可表示为： How much is two plus three?
2+3=5
Two plus three is five.
Two and three is equal to five.
Two and three make five.
Two added to three equals five.
If we add two to/and three, we get five.
二加三等于五
2. 减”用 minus或 take from表示
10-6=? How much is ten minus six?
10-6=4
Ten minus six is four.
Take six from ten and the remainder is four.
Six (taken) from ten is four.
十减去六等于四
3. 乘”用time(动词)或multiply表示
3X4=? How much is three times four?
3X4=12
Three times four is/are twelve.
Multiply three by four，we get twelve.
Three multiplied by four makes twelve.
三乘以四等于十二
4. 除”用divide的过去分词形式表示
16÷4=? How much is sixteen divided by four?
16÷4=4
Sixteen divided by four is four.
Sixteen divided by four equals/gives/makes four.
十六除以四等于四。
五、分数表示法
1. 分数是由基数词和序数词一起来表示的。基数词作分子，序数词作分母，除了分子是1”以外，其它情况下序数词都要用复数形式。
3/4 three fourths或 three quarters
1/3 one third或a third
24/25 twenty-four twenty-fifths
3 1/4 three and one fourth或 three and one quarter
1/2 a half
1/4 one quarter或a quarter
1 1/2 one and a half
1 1/4 one and a quarter
2. 当分数后面接名词时，如果分数表示的值大于1，名词用复数;小于1，名词用单数。
1 1/2 hours 一个半小时(读作 one and a half hours)
2 3/4 meters 二又四分之三米(读作two and three-fourths meters)
4/5 meter 五分之四米
5/6 inch 六分之五英寸
3. 表示n次方”的说法：指数用序数词，底数用基数词。
10的7次方 the seventh power of ten(ten to the seventh power)
6的10次方 the tenth power of six(six to the tenth power)
