I am trying to get my head round plurals. I have read some articles and it seems complex. Could one of you lovely people explain it for a beginner like me?
OK so there are several plural endings in Gaelic.
You can slendarise an ending as in balaich, or you can ad an or aichean to the ending.
Unfortunately there isn't really a rule for which ending you use but as a general rule of thumb if the word is long it gets a shorter plural suffix and if it's short it'll often have a longer ending. Unfortunately it's just something you'll have to memorise but people will forgive the error in conversation.
Here is a link which explains in way more detail.