Learn Dutch: Waren we maar thuis gebleven! - If only we had stayed home!

This is an optative exclamation, which expresses a strong wish or regret. In Dutch, you can form these by putting the verb first (just like a yes/no question) and adding a modal particle like maar. Together, the verb-first structure and maar translate to "If only..." in English.

The English translation says "had stayed", so why does the Dutch sentence use waren (were) instead of hadden (had)?

In Dutch, verbs indicating a change of state or motion, as well as a few notable exceptions like blijven (to stay) and zijn (to be), use zijn as their auxiliary verb in the perfect tenses. Since blijven takes zijn, the past perfect "had stayed" must be translated as waren gebleven.

Could I use the particle toch instead of maar here?

Yes! You could say Waren we toch thuis gebleven! and it would mean exactly the same thing. In these verb-first wishes, maar, toch, or even a combination of both (toch maar) are used to provide the "if only" feeling.

How would I change this sentence to say "If only we were staying home!" (a wish about right now)?