bet的过去式和过去分词

　　My bet is that they've been held up in traffic.

　　我估计他们是堵车了。

　　If you want to get around London fast, the Underground is your best bet.

　　如果你想在伦敦快速出行，最好是乘地铁。

　　You can bet your bottom dollar that he'll be late.

　　他肯定会迟到。