Learn Italian: Ci sono settanta alberi là. - There are seventy trees there.

Like many tens in Italian, settanta is based on the single digit. It comes from sette (seven). For numbers 40 through 90, you generally take the root of the single number and add -anta. So, sette becomes settanta.

Does the ending of settanta change because alberi is a plural masculine word?

No. In Italian, cardinal numbers from two onwards (like settanta) are invariable. This means their endings never change to match the gender or number of the noun they describe. It will always be settanta, whether you are counting masculine alberi (trees) or feminine persone (people).

The sentence has ci sono and là. Don't they both mean 'there'?

Yes, but they do different jobs! Ci sono is a fixed phrase meaning 'there are' (stating that something exists). Là refers to a physical location, meaning 'over there'. In English, we use the word 'there' for both purposes, but Italian uses completely different words to avoid confusion.

Why does là have an accent mark on the 'a'?