Learn French: Il est dix heures, tu dors beaucoup ! - It is ten o'clock, you sleep a lot!

In French, you use beaucoup (a lot) to intensify a verb. Here, it describes the action of sleeping (dors). You only use très (very) to intensify adjectives (like "tall") or adverbs (like "fast"). Since sleeping is an action, beaucoup is the correct choice.

Why does the sentence use Il est instead of C'est for "It is"?

When telling the time in French, you must always use Il est. Even though C'est also means "It is" and is used to identify things in many other situations, telling the time is a strict exception!

Since dix heures is plural, why isn't the beginning of the sentence Ils sont?

Even though ten hours is plural, the Il in Il est is an impersonal pronoun here, exactly like the "It" in the English phrase "It is raining". It doesn't refer to a specific plural object, so the verb stays strictly singular.

How are the words dix heures pronounced together?

Because dix ends in an "x" and heures starts with a silent "h", their sounds link together (a rule called liaison). The "x" changes to a "z" sound, making dix heures sound like "deeze-uhr". The "s" at the end of heures remains silent.