I'm a little bit confused about the usage of 'by+numeral" in the following sentence:
[a teacher to students] Now you're going to work by three... Okay, I see there're four of you over there, so you can work by four.
Is it possibe to change "in pairs" --> "by two", "in groups of three" --> "by three" etc?
Thank you in advance.
The usual expression, certainly here in the UK, is "You're going to work in twos (or pairs)", or threes, or fours". I doubt you'd ever hear anyone say "..by...".