Вставьте слова в предложения: roadworks, off , underground, pedestrian, helicopter

A ________ is an aircraft that uses rotating wings called blades to fly.
The ___________ is a railway system in which electric trains travel mainly below the ground.
There are delays on our main motorway because of ______________ .
A _______________ is a person who is walking in a street.
Is this Mayakovskaya Street or should I get _______________ at the next stop?