'flight' means ' a set of stairs between one floor and the next'. 'stairs' means 'thought of as a group esp. as forming a flight or a series of flights'. As far as I understand when 'stair' is in plural it means 'flight'.
Please read the sentence:
He ran down the four ________ and through the wide doors of the ground floor entrance.
a. flights b. stairs
The key is 'a'. My question is: why isn't 'b' correct?
Looking forward to hearing from you.
Thank you in advance.