You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

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?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?

How can you take 2 from 5 and leave 4?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

John enters a small room. The Door Closes.
When the door opens, John is in a larger room.

Explain?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

Fate has decided that you will only be pleased to meet me when you need me

Maybe that is why, when I am working, I start working

However annoying I may be to the regulars, the little ones are always inspired

I will always be waiting if you try to reach me

How many of you can guess my name, let me see