How many seasons are there in one year?
4 estaciones
This is a question sentence and it means "How many months does one year have". (Cuantos = How many; meses = months; hay = there are; en = in; un = one; ano = year).
"How many days are there in a year?"
Hay cuatro estaciones al año: primavera, verano, otoño e invierno. Cada una tiene características distintas en cuanto a clima y duración.
How many weeks are in a year? 52...
it means "how many years is it?" or "..... are there"
It means"How many teachers are there?"
Hay 365 días en un año común y 366 días en un año bisiesto.
If the sentence says "¿Cuántos días hay en un año? it means "How many days are there in a year?" If it says "¿Cuántos días hay en una semana? it means "How many days are there in a week?"
It means "How many seasons are there in a year?"
"¿Cuantos dias hay en septiembre?" is Spanish for "How many days are there in September?"
That means "How many are there in an hour?"