Learn Portuguese (Portugal): Há ali uns cadernos novos. - There are some new notebooks there.

In Portuguese, the indefinite articles um (masculine) and uma (feminine) have plural forms: uns and umas. While English does not have plural indefinite articles, in Portuguese they translate perfectly to 'some' or 'a few'. Since cadernos is a masculine plural noun, we use uns.

Could I use alguns instead of uns to say 'some notebooks'?

Yes, uns and alguns are very similar and both mean 'some'. Uns is often used to introduce new items into a conversation (like 'a few' or 'a couple of'), while alguns can sometimes sound a bit more specific, like 'some, but not all'. At this beginner stage, you can think of them as mostly interchangeable.

Doesn't Há mean 'There is'? Why is it used here for 'There are'?

The verb form Há (from the verb haver) is incredibly useful because it means both 'there is' and 'there are'. It never changes form, no matter how many things you are talking about. So, Há um caderno means 'There is a notebook', and Há uns cadernos means 'There are some notebooks'.

I thought the word for 'there' was lá. What is the difference between lá and ali?