Learn Dutch: De programma's beginnen 's avonds laat. - The programs start late in the evening.

Dutch uses an apostrophe for plurals when a noun ends in a single open vowel, like "a", "i", "o", "u", or "y". This prevents the pronunciation from changing. If we just wrote "programmas", the rules of Dutch spelling would make the final "a" sound short. The apostrophe keeps the "a" sounding long.

The phrase 's avonds also has an apostrophe and an "s". Is that a plural too?

No, this is a completely different grammar rule! The 's in 's avonds (and 's morgens, 's nachts) is an abbreviation of an old Dutch word des, meaning "of the". So 's avonds literally means "of the evening", or as we say in English, "in the evening". It has nothing to do with plural nouns.

Why does laat go at the very end of the sentence?

In Dutch, expressions of time like 's avonds usually come before other adverbs like laat (late). The sentence literally flows as "The programs start in the evening late."

What if a word ends in an "e"? Does it get an apostrophe-s plural like programma's?

No, words ending in a single "e" usually just get an "s" without the apostrophe, like kamers (rooms) or meisjes (girls). The apostrophe is only used for "a", "i", "o", "u", and "y" to protect their long vowel sounds. Since a single "e" at the end of a word is usually a short "uh" sound, it does not need protecting.