Breakdown of Les trésors précieux qu'ils cachent sont très anciens.
être
to be
très
very
ils
they (masculine/mixed)
cacher
to hide
Questions & Answers about Les trésors précieux qu'ils cachent sont très anciens.
Why is it qu' here instead of qui?
In this sentence, qu' is the shortened form of que (meaning "that"). We use que because the treasures are the object being hidden, while ils (they) is the subject doing the hiding. You would use qui only if the treasures themselves were doing the action. We drop the "e" and add an apostrophe because ils starts with a vowel.
Why doesn't précieux have an extra "s" at the end to match the plural trésors?
I notice précieux comes after trésors. Don't some adjectives come before the noun?
Do I need to pronounce a liaison between très and anciens?