in the next seven years (meaning of in in this context)

Question

I am very confused with the phrase ' in the next seven years '. The full sentence is "Before discussing the type of technology that will be at play in the future, take a quick look at what might be expected in seven years and then in the more distant future."

In this case, does this mean that it will happen after 7 years? or within 7 years?

I am very confused with 'in' in this context. Then, a new sentence says 'There will be considerable change over the next five years.'

Does this mean that 'in' is interchangeable with 'over'?

Answer 1

In

Used to indicate inclusion within or occurrence during a period or limit of time.

-- Dictionary.com

In this case, does this mean that it will happen after 7 years? or within 7 years?

As you can tell from the above definition, the sentence is referring to what will happen between now and seven years time, not after seven years time. The event could be in one year, one day, six years and eleven months... Any point in time between now and seven years hence.

Over

During; through, or throughout (a period of time)

--Dictionary.com

Does this mean that 'in' is interchangeable with 'over'?

Yes. As you can tell from the above definitions, in this context, the two words mean the same thing.