I get the feeling that cheese and pasta is a common meal in Ireland based on how many times I've translated it this course :3
Why do they let us leave comment's anyway ?
So that a commenter’s questions can be answered.
The only answer on she is sí
Yes? What else was offered as correct?
Why can't 'si' go to the end of the sentence as in Itheann cais agus pasta si?
Because the subject of the sentence follows the verb and precedes the objects.
Is this where the English word for cheese comes from? In French, fromage and Spanish, queso so I doubt that the word cheese comes from there.
No; “cheese”, cáis, and queso all originate in Latin caseus.
Also "Käse" in German.
There's also Caws in Welsh, which is also a Celtic language, so it might be.
Is it necessary in Irish to explicitly state the pronoun, or could you just say "itheann cáis agus pasta" ?
You must explicitly state the pronoun.
The exception is if you are answering "Yes" to a question, where you can just repeat the verb, without a subject or an object: An itheann sí cáis agus pasta? Itheann
Would 'Itheann cais agus pasta i' by incorrect?
Yes, it would be incorrect, as it would make cáis agus pasta the subject of the verb, rather than the object.