Bac
abbr. 二进制模拟转换（Binary-Analog Conversion）；（美国）波音飞机公司（Boeing Airplane Company）；英国飞机公司（British Aircraft Corporation）
🗣️ 情景例句
That's it.
对啦
Where the knot is loose the string slips.
结子一松掉，绳子就滑脱。
is the slowest and has travelled round the earth through the surface rocks.
是最慢的，是围绕地球通过表面岩石传来的。