Backchannel
（传递消息的）秘密渠道, 特殊途径
🗣️ 情景例句
in the school and loving every minute of it.
在学校 ，且乐此不疲， 时时如此。
To learn how to count
学习记账
Their interest is listening to others.
他们的兴趣是听别人说话。