What am I?

I am commonly abbreviated to H. What am I?

Like a river I flow, and you’re happy I do in vain. There is no escaping from my course, without causing pain. What am I?

I am pronounced as one letter, written with three. I come in blue, black, brown, or grey. Reverse me and I read the same either way. What am I?

There are four of us, but it seems like everyone loves spades the most. What am I?

Riddles and Answers