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Example
這項研究採用縱向方法，追蹤同一批學生十年。
这项研究采用纵向方法，追踪同一批学生十年。
The study uses a longitudinal method to follow the same group of students for ten years.
Usage Notes
In research, this describes following the same people or subjects over time. It can also mean vertical or lengthwise, in contrast with a crosswise direction.
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