Learn Portuguese (Portugal): Eles são os médicos novos.

Not necessarily! Eles is used for a group of men, but also for a mixed group of men and women. You would only use elas if you knew for sure that every single doctor in the group was a woman.

What does the squiggly line over the 'a' in são do?

That mark is called a tilde, and it tells you to make a nasal sound, as if you are speaking through your nose. São sounds a bit like the English word 'sound' without the 'nd' at the end. It is the plural 'they' form of the verb ser (to be).

Why do os, médicos, and novos all end in 's'?

In Portuguese, all the words connected to a plural noun have to match it! For most words ending in a vowel, you just add an 's' to make them plural. Since médico is a masculine noun, the word for 'the' becomes the plural os, and the adjective novo also adds an 's' to become novos.

Why are the words in the order médicos novos instead of novos médicos?

In Portuguese, adjectives (descriptive words like novos) usually come after the noun they describe. So, instead of saying 'new doctors' like we do in English, you literally say 'doctors new'.