What country can make you shiver?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

During which month do people sleep the least?

Why do people go to bed?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

Can you make the below equation true by using any three numbers from "1, 3, 5, 7, 9, 11, 13 and 15"?

( ) + ( ) + ( ) = 30

How many times can you subtract the number two from the number fifty?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

I don't get anymore wetter, no matter how much rain falls on me.