Learn French: Les chiens aiment la compagnie, tandis que les chats préfèrent être seuls. - Dogs like company, while cats prefer being alone.

Yes! Both tandis que and alors que mean "while" or "whereas" when comparing two contrasting ideas. They are practically interchangeable here. Tandis que can sound slightly more formal, but both are perfectly normal in everyday French.

In English, we just say "Dogs like company." Why does French add les and la?

In French, you must use definite articles (le, la, les) when talking about things in a general sense. Since this sentence is about dogs, company, and cats in general, you need les chiens, la compagnie, and les chats.

Wait, the infinitive is préférer, so why does préfèrent have a grave accent (è)?

Préférer is a stem-changing verb. For pronunciation reasons, the second acute accent (é) changes to a grave accent (è) whenever the verb ending is silent. Since the -ent ending for the plural "they" form is silent, it becomes préfèrent.

Why does seuls have an s at the end?