I will take a little rest.

When an object is in free fall, its terminal velocity is determined by the balance between gravity and air resistance.

An irregular galaxy is a type of galaxy that does not have a definite shape.

He sent a reminder letter about the unpaid charges.

This new jet can fly at supersonic speeds.

His hobby is astronomical observation.

I can't keep up with his irregular schedule.

I measured the wind speed using an anemometer.

We hired a professional to survey the new land.

Please send it by express delivery.