Which preposition should I use? IN or ON?
Runners sped up in/on ? the track with all their might .
There's a little boy roaming in/on ? the field.

Thanks:)

Question

Which preposition should I use?  IN  or  ON?
Runners sped up in/on ? the track with all their might .
There's a little boy roaming in/on ? the field.

Thanks:)

Answer

For the second one, I would say:

For location: The boy is  in the field.

For activity: The boy is running on the field.

Answer

Yes, it is normal to say  "the boy is running in the race".  Is that your question?.

Answer

Thanks Patrick!!! You've made it clear .  
And I want to ask whether 'in the track' exists.  
Here's the sentence-- ' Athletes are running in the ___(track/field) '. 
The context is that athletes are competing in a race,which means that they are supposed to be 'running ON the track ' ,but the preposition given is IN, and it makes me hesitate.

Answer

1) Runners sped up on the track.
2) There's a little boy in the field.
However, #2 could go either way.  If it is a field of flowers, then I would say "in the field". However, if it is a baseball field then I would say "on the field". But just to make it more confusing, for sports fields sometimes we say "he is in the field of play".
I hope that helps :)

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