Learn Spanish (Spain): Mi abuelo tiene noventa años y está muy sano. - My grandfather is ninety and is very healthy.

In Spanish, you use the verb tener (to have) to express age. Instead of saying someone "is" a certain age, you literally say they "have" those years.

Why is the word for ninety noventa instead of nueventa?

While the number nine is nueve, the tens drop that extra vowel sound. Just like seven is siete but seventy is setenta, nine becomes noventa.

Why do we use está instead of es for "is very healthy"?

We use estar because physical health is treated as a state or condition. If you used ser sano, it would describe someone who leads a healthy lifestyle or a thing that is good for you (like healthy food). Estar sano means his body is currently in good health.

What happens if I forget the accent mark on está?

The accent mark is crucial because it changes the word completely. Está is a verb meaning "he is" or "it is", while esta without the accent means "this" (as in esta familia). The accent also tells you to stress the final syllable when speaking.