Ielts
abbr. 雅思（The International English Language Testing System）
🗣️ 情景例句
Do you think it's too long?
你会不会觉得太长了？
It's a pain in the neck.
那真是件麻烦事
a wave length (the horizontal distance between two wave crests),
波长（两个浪峰间的水平距离）