Questions & Answers about Слева от нас был старый сад.
Why do we need от here instead of just saying слева нас?
Слева is an adverb meaning "on the left", not a preposition. To connect it to an object and say "to the left of" something, you must use the preposition от (from). So слева от нас literally translates to "on the left from us".
Why is мы (we) changed to нас in this sentence?
Нас is the Genitive case form of мы. The preposition от always requires the Genitive case. You are seeing a lot of the Genitive case in this lesson because it is heavily used to describe spatial relationships, just like with the prepositions вокруг (around) and вдоль (along).
I always confuse слева and налево. Could we use налево here?
No, because they answer different questions. Слева answers "where?" (где?) and indicates a static location (on the left). Налево answers "where to?" (куда?) and indicates motion or direction (to the left, like when turning). Since the garden is just sitting there statically, we use the location word слева.
Why is the subject (старый сад) at the very end of the sentence?