four jets in the sky
a plane in air
a plane flying in air
a group of planes
number of planes in air
four planes in the sky
four planes in the air
four planes flying together
four planes flying in formation 
four planes flying as a team
two planes in front
two planes in back
four planes going the same way
Four airplanes are in the picture.
Two airplanes are to the left.
Two airplanes are to the right.
an airplane flying through the blue sky with four propellers