常规表达：increase rise grow edge up
短语表达：experience an/a increasing/upward trend/tendency
常规表达：decrease drop fall decline edge down
短语表达：experience a decreasing/downward trend
常规表达：remain stable keep unchanged stabilize stay constant
experience ups and downs
剧烈：great sharp huge significant dramatic rapid obvious
平缓：gradual steady stable consistent constant
小幅：slight marginal minimal
The figure for Japanese aged over 65 decreased sharply. 主谓宾结构
There was a great fall in the number of Japanese aged over 65. There be句型
The amount of Japanese population aged over 65 showed a downward trend.
The period from 1990 to 2000 witnessed a downward trend in Japanese
population aged over 65. 考官范文最喜欢用的句型
The spending on teachers' salaries always occupied/accounted for the most significant share of this school's expenditure.
The average amount of time spent on playing PC games on a daily basis was half-hour higher than that on watching TV.
Playing PC games cost half-hour more every day on average than watching TV did.
There was half-hour more time on playing PC games every day on average than watching TV.