1、趋势类词汇
上升动词类：increase，go up，rise up，grow up，jump up，surge，shoot up，keep an upward tendency
下降动词类：decrease，go down，decline，fall down，drop，sink，dip，keep a downward tendency
波动动词类：fluctuate
持平动词类：remain the same，stabilize，remain stable，remain constant
修饰动词的副词：slightly 轻微地，slowly 缓慢地，gradually 逐渐地，steadily 稳定地，rapidly 迅速地，moderately 温和地，轻微地，significantly 明显地，sharply 明显地，dramatically急剧地，drastically 急剧地
上升名词类：increase，rise，growth，jump，surge
下降名词类：decrease，decline，fall，reduction，drop
波动名词类：fluctuation
修饰名词的形容词：slight，slow，gradual，steady，rapid，moderate，significant，sharp，dramatic，drastic
2、极值类词汇和表达
最高点：reach the peak/top/highest point
Increase to the peak/top/highest point(所有上升类的动词都可以替换掉increase)
最低点：reach the bottom/lowest point
drop to the bottom/lowest point(所有下降类的动词都可以替换掉drop)
占的最多： occupy/make up/take up/account for the largest proportion/number/percentage of …
占的最少：occupy/make up/take up/account for the smallest proportion/number/percentage of …
3、倍数的表达方式
Double 是两倍/大一倍
Increase/decrease three times 增长/减少了三倍
4、大约的表达方式
About/around + 数字
数字 + or so
Approximately + 数字
5、常用的小作文的趋势句式表达
句式一： 变化主体/图画中主体+趋势动词+副词+时间区间
Eg: The number of aged people over 65 increased significantly from 1940-2000.
The number of aged people over 65 dropped slightly from 1960-1980.
The number of aged people over 65 fluctuated between 1 million and 1.2 million from 1940-1950.
The number of aged people over 65 remained stable from 1930-1940.
句式二： There be + 形容词 + 表示趋势的名词 + in+ 变化的主体+ 时间区间
Eg: There was an significant increase in the number of aged people over 65 from 1940-2000.
There was a slight decline in the number of aged people over 65 from 1960-1980.
There was a fluctuation between 1 million and 1.2 million from 1940-1950.
