What is so fragile that saying its name breaks it?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

There are 2 cops parked along a one-way street looking for traffic violations. They spot a taxi driver going in the wrong direction, yet they do nothing.

Why?

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

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

What goes up but never comes down?

I taste better than I can smell. Who am I?

Which of the following words don't belong in the group and why?
CORSET, COSTER, SECTOR, ESCORT, COURTS

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?