C、表编号：
第207房间：Room 207
第五课： Lesson 5 = the fifth lesson
D、序数词与不定冠词(a; an)连用表“又一;再一”
eg. You’ve done it three times. Why not try a fourth time?
E、分数的表达：分子(基数)、分母(序数)
eg. one third 三分之一 two thirds 三分之二
注意：
1.分子超过1时，分母加s
2.含分数的短语作主语由分数后的词决定谓语
eg.1)One third of the students are girls.
2)One third of the milk is mine.
3.分数的特殊形式
1)one third = a third
2)one fourth = a quarter
three fourths = three quarters
3)one second = a half
F、表约数：
表不确定的数字时，数词用复数。
若带名词，再加of
如：hundreds of(数百，成百上千的)，thousands of(数干，成千上万的)，millions of(数百万的)
G、数学运算的表达
eg.3+5=8 Three plus/and five is eight.
9-2=7 Nine minus two is seven.
6x5=30 Five times six is thirty
8÷2=4 Eight divided by two is four.