Исправьте ошибки в построении предложения :
Do you wait for the bus at the moment?
It's snowing every winter in my country.
What he doing now?
How many Noble Prize winner there were?
They were hundreds of people at the concert.
Was you at school yesterday?

1. Are you waiting for the bus at the moment? Здесь используется Present continuous, потому что есть указатель времени - at the moment 
2. It snows every winter in my country. Используется Present Simple, потому что EVERY WINTER - действие повторяющееся, каждый год, каждую зиму.
3.  What is he doing now? - NOW - указатель на Present Continuous.
4. How many Noble Prize winner there had been? - Здесь уже Past Perfect
5. ??? 
6. Have you been at school yesterday? - yesterday указывает на Present Perfect