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

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

You want to boil a two-minute egg. If you only have a three-minute timer (hourglass), a four-minute timer and a five-minute timer, how can you boil the egg for only two minutes?

I have branches, but no fruit, trunk or leaves. What am I?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

A non-stop marathon is the shared favourite sport of three brothers.

*The oldest one is fat and short and trudges slowly on.
*The middle brother's tall and slim and keeps a steady pace.
*The youngest runs just like the wind, speeding through the race.

"He is young in years, we let him run!" the other two brothers explained, "'because though he is surely number one, he is second, in a way." Why is it?

I am lying and I always lie. Tell me whether I am lying or telling the truth.

I look at you, you look at me I raise my right, you raise your left. What am I?

How can one talk without saying a single word?