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[计] 先根次序
✅ 同义词
🗣️ 情景例句
The old library building on Chestnut Street,
Chestnut街老图书馆，
What? I'm right, aren't I?
怎样？我没说错吧！
a wave length (the horizontal distance between two wave crests),
波长（两个浪峰间的水平距离）