葛乾
一、小数表示法
A.小数用基数词来表示,以小数点为界,小数點前的整数部分按数目整体读,小数点后应一位数一位数来读。小数点读作point,0 读作zero 或O,整数部分为零时,可以省略不读。如:0.5 读作zero(O) point five; 或point five,3.14 读作three point one four.
B.当数字值大于1时,小数后面的名词用复数;数字值小于1时,小数后面的名词用单数。如:
1.03 meters 1.03米 0.56 ton 0.56吨 6.8 tons 6.8吨
二、分数的表达法
A.分子用基数词,分母用序数词。分子大于1时,分母的序数词要加“s”。如:读作one third; 读作two thirds;
2 读作two and two thirds;
读作twenty-four twenty-fifths
读作 a half 或one half 表示;
可用one fourth,也可用a quarter 或one quarter表示;
B.在语句中表示“几分之几的……” 要与介词of 连用,
的学生 one third of the students.
C.当分数后面接表示单位量的名词时,如果分数表示的大于1,名词用复数;小于1,名词用单数。如:
1 hours 一个半小时,2 meters 二又四分之三米
meter五分之四米
三、百分数表示法
百分数用“基数词+percent” 表示,无论基数词多大,percent 都不加-s。如:5%读作five percent;
0.12% 读作zero point one two percent
表示“百分之几的……”要与of 连用。
如:30%的学生:
30% of the students 或thirty percent of the students
四、加减乘除表示法
A.“加“用plus表示“等于”用equals; is equal to; is; makes等词表示。
2+3=?How much is two plus three?
2+3=5 Two plus three is (equals; is equal to; makes) five
B.“减”用minus 表示。
8-3=?How much is eight minus three?
8-3=5 Eight minus three is ( equals; is equal to ; makes) five
C.“乘”用times 或multiplied by表示。
3×3=? How much is three times three?
3×3=9 Three times three is (equals; is equal to; makes)nine.
Three multiplied by three is nine.
D.“除”用divided by 表示。
16÷4=?How much is sixteen divided by four?
16÷4=4 Sixteen divided by four is four.
五、一些计算式
(1) x2 读作 x squared 或x to the second power 或the second power of x
32=9 Three squared is nine; The second power of 3 is 9;
Three to the second power is nine;
x3 读作x cubed 或x to the third power 或the third power of x
33=27 Three cubed is twenty-seven;
Three to the third power is twenty-seven;
x4 读作x to the fourth power 或the fourth power of x
34=81 Three to the fourth power is eighty-one.
(2) the second root of x 或the square root of x
=3 The second square root of 9 is 3;
=3 The third (cube) root of 27 is 3;
=3 The fourth root of 81 is 3.