To be lost in the cloud

A black sheep

To cool one's heels

To carry the coal to Newcastle

Sumit had to look <u><em>high and low</em></u> before he could find his scooter key.

To make the grade

Chandu used very ugly words against his kind uncle; he <u><em>threw down the gauntlet</em></u> b…

He has accomplished a <u><em>Herculean task</em></u>.

The number of <u><em>globetrotters</em></u> has increased after the Second World War.