periodic patterns的用法和樣例：
例句
- The likelihood of a net fiscal drain from emigration is raised by the life-cycle patterns of public goods and migration.
公益設施和移民的生命周期模式，使得由出境移居而造成財政凈流出的可能性增大了。 - Thus every motion corresponding to any initial curve is no more than a sum of sinusoidal periodic modes.
這樣，每一個對應於任一初始曲線的運動不外乎是正弦周期模式的和。
