The phrase "a certain stretch of" is correct and usable in written English.
It can be used to refer to a specific period of time or a particular extent of something, often in a vague or non-specific manner.
Example: "During a certain stretch of the summer, we traveled across the country visiting various national parks."
Alternatives: "a specific period of" or "a particular span of".
A certain stretch of river bank there has a castle every mile.
Are the sensors on many vehicles measuring a severe shock on a certain stretch of road?
For a certain stretch of time, pervasive sexism in the industry meant that the commercial history of rock music with a handful of notable exceptions was largely male.
Today, he is a plumber and organic farmer (I bought some lovely cucumbers and tomatoes from his stand for 3.25 dollars) and can remember when a certain stretch of road had been a meadow.
Why do birds in flight suddenly stop to rest on a certain stretch of telephone wire?
The team spotted one suspicious-looking B. pseudomallei protein, BPSL1549, which, along a certain stretch of its structure, resembles an enzyme common in Escherichia coli bacteria.
Now that we understand that we can play that way and get through a certain stretch in the beginning of the game or the middle of the game, we know that our skills and the guys we have and style we'd like to play will eventually come out if we work hard defensively and work hard for each other.
TMS provides KH with legitimacy to operate tow trucks for certain stretch of road.
A computer search turned up certain stretches of a key part of the H1N1 virus, the hemagglutinin protein, that "looked strikingly the same" as the hypocretin epitopes, Mignot says.
This analysis was based on a molecular clock, the idea that in certain stretches of DNA or RNA, mutations accumulate at a reliable rate (e.g., one per year), allowing them to be used as timers: the more mutations the genetic material has accumulated, the longer since it split off from its ancestral sequence.
The River Mersey forms Didsbury's southern and southwestern boundaries and certain stretches of the river also demarcate the boundaries of the City of Manchester.
