In the following question the 1st and the last part of the sentence/passage are numbered 1 and 6. The rest of the sentence/ passage is split into four parts and named P, Q, R and S. These four parts are not given in their proper order. Read the sentence/passage and find out which of the four combinations is correct

1. Suddenly the man heard the low hum of an engine.

P. Instead, it grew louder and louder and seemed to be coming from above.

Q. At first he thought that it must be a car travelling along the road he had recently left.

R. He looked up quickly and saw an aeroplane cutting a crazy, zigzag path across the sky.

S. He expected the noise to fade away in the distance.

6. It disappeared for an instant behind some clouds, then emerged and plunged into the field.