Babysitters
声音指示器
🗣️ 情景例句
Do you remember when Daddy and I used to take you
你还记得爸爸和我常带你
You were late again this morning. I think you had better start being on time.
你早晨又迟到了，我想你最好开始守时。[托福]
a wave length (the horizontal distance between two wave crests),
波长（两个浪峰间的水平距离）