Learn Dutch: We zijn moe.

We is the unstressed, everyday version of wij. In Dutch, you use we for most normal sentences, unless you specifically need to put emphasis on "we" (like saying "WE are tired, but THEY are not").

Why is the verb zijn used here? Isn't that the dictionary form (infinitive)?

Yes, zijn means "to be". In Dutch, the present tense verb for all plural subjects (we, jullie, and ze) is exactly the same as the infinitive. So "we are" translates to we zijn.

Since we is plural, shouldn't the adjective moe get an extra -e at the end?

No. When an adjective comes directly after a verb (like "is" or "are") to describe the subject, it never changes its ending. It stays moe whether you are talking about one person or many people.

How do I pronounce moe?

The Dutch letter combination oe sounds very much like the English "oo" in "moo" or "shoe".