Well, in one of our engineering classes of Telecommunication and Switching, our teacher was explaining to us about the different connection types in a switching network. She was counting the switches at one point as, "one, two, three, four, five, sex".. (lol!).. and actually nobody realized coz most of us were busy talking or doing our own stuff. Only one of the first-benchers realized and started giggling. She became all apologetic suddenly and word started spreading around the same time that she had spoken as above.. Only then did the whole class start laughing... This went on for about 5 min atleast.. She couldn't look at us after that for quite a while.. lol!
The bench on which I was sitting was a little late in knowing what happened and consequently, we laughed quite late.. She chucked us out as she thought it was persistent laughing! :rofl: