We use in to say how long it takes someone to do something:
He was such a clever musician. He could learn a song in about five minutes.
We use an apostrophe -s construction (in a year’s time, in two months’
time) to say when something will happen. We don’t use it to say how
long someone takes to do something:I won’t say goodbye because we’ll be seeing each other again in three days’ time. We can also say in three days, without time, in this
example.He ran the marathon in six hours and 20 minutes.
Not: He ran the marathon in six hours and 20 minutes’ time.
in:- during a period of time
in 2009
in the 18th century
in spring/summer/autumn/winter
in the fall
in March
in the morning/afternoon/evening
I'm getting forgetful in my old age.
in:- after a particular length of time
to return in a few minutes/hours/days/months.
It will be ready in a week's time (= one week from now).
She learnt to drive in three weeks (= after three weeks she could
drive).
so, Does Cambridge Grammar mean?
He could learn a song in about five minutes.=He could learn a song during about five minutes.?
&
we’ll be seeing each other again in three days’ time= we’ll be seeing each other again after three days?
So, "in 5 minutes" means either "during 5 minutes" or "after 5 minutes" right?
Best Answer
In Oxford's definition, "after a particular length of time" can be thought of as "after a particular length of time has elapsed."
So:
basically means:
As for:
a good substitution preposition for this would be within:
Another way we could convey this is:
As for during, think of that as "at some point in time during a specified interval".
Therefore:
means:
And:
means:
Bottom Line: in cases where in means during, that doesn't mean within some interval of time (such as in five minutes, or in two days), but rather for a more specific range of time (such as in the first week of the month, in December, or in the 18th century, or even in the early hours of the morning).