No one has ever pronounced b in it, and it is absent from the word’s Old English form and from its cognates, such as Dutch duim and German Daumen.
它中间的b从来就没有发过音，并且b在古英语的形式中，及其它同源词如荷兰语duim和德语Daumen里都没有。
Why were you absent from lessons last month? B: I was stuck in a vicious circle. A: Oh, what happened to you?
你为什么上个月缺课了？ b：我陷入到恶性循环之中。A：哦，到底发生了什么事儿？
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