Bb
abbr. 滚珠轴承（ball bearing）；铅笔芯（double black）
🗣️ 情景例句
Why don't you join us?
你何不参加入我们呢？
I don't have the time for any more extra-curricular activities.
我没有更多的时间从事课外的活动了。
'It's all right,' she said, 'but isn't it upside down?'
是不错，她说到，但你不觉得有些混乱吗？