Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

What country can make you shiver?

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

Katniss and Peeta are liars. They both lie on some specific days.

Katniss lies on Fridays, Saturdays and Sundays. She speaks the truth on all other days.

Peeta lies on Tuesdays, Wednesdays and Thursdays. He speaks the truth on all other days.

Can you tell that one day of the week when both of them will say "Tomorrow, I will lie."?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Remove two matchsticks to make the below equation correct.

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

A clock loses 10 minutes each hour. If the clock is set correctly at noon, what time is it when it reads 3 PM?