"They run for the street" doesn't really make sense. That would imply they are running on behalf of the street. Normally, when you do anything "for" or "on behalf of", you're doing it for an animate object, like a person or an animal or a cause. (e.g., "I am running in the race for my son." or "I am running in the race for a cure to cancer.")
Actually, there are at least two meanings to "they run for the street" that can make sense.
- "They are running towards the street"
- Taking "the street" to mean a certain community, "they run for the street" can mean that they are their street's team in some running competition.
For both of those cases, "they are running for the street" would sound better. "They run for the street" sounds unfinished, like it needs a comma and a bit more info (eg "they run for the street, jumping over tables along the way")
Would "They run along the the street" be ok here? In English, I would normally only say "they run on the street" if I wanted to highlight the surface, eg in contrast to running on the footpath, or running on grass.
Given the three choices given for "pela" is not "by" the best answer- by being short in English for "by the way of" or "by the means of" the street?
Is there a significant difference between using pela and na in this sentence?
Not much, but it's something like:
- Eles correm pela rua = They run around the street, or they run through the street.
- Eles correm na rua = They run on the street.
"Na" is a contraction of "em a" (in the, on the, at the), While "pela" is a contraction of "por a" (by the, for the, through the).
As an aside, the translation "they run along the street" is also accepted here.