Они никогда не забывают ключи.

They never forget keys.

Breakdown of Они никогда не забывают ключи.

• ключ: the key
• они: they
• никогда: never
• забывать: to forget

Questions & Answers about Они никогда не забывают ключи.

Why is there both никогда and не in the sentence? It seems like double negation.

In Russian, negative adverbs like никогда (never) must be paired with the negative particle не on the verb. You always say никогда не забывают rather than dropping не. Together they express a single negation (“never forget”).

There’s no word for their before ключи. How do you express “their keys”?

Russian often omits possessives when context makes ownership clear. If you want to specify, use the reflexive possessive свои (their own):
• Они никогда не забывают свои ключи.
You could also say их ключи, but with the subject as owner, свои is more natural.

Why aren’t there any articles like the or a before ключи?

Russian does not have articles. Whether ключи is “keys,” “the keys,” or “some keys” is determined by context, word order, or additional words (like эти for “these keys,” etc.).

What case is ключи in, and how do you tell?

Ключи is in the accusative plural (direct object). For inanimate nouns, the nominative and accusative plural look the same, so you rely on word order (noun follows the verb) and meaning to see it’s the object.