Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

If you say my name, I will no longer exist. What am I?

Which is the correct shadow of the bird?

A monk has a very specific ritual for climbing up the steps to the temple. First, he climbs up to the middle step and meditates for 1 minute. Then he climbs up 8 steps and faces east until he hears a bird singing. Then he walks down 12 steps and picks up a pebble. He takes one step up and tosses the pebble over his left shoulder. Now, he walks up the remaining steps three at a time which only takes him 9 paces. How many steps are there?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

What month of the year has 28 days?

If an electric train is travelling south, then which way is the smoke going?