Questions & Answers about В корзине лежат огурцы, помидоры и картофель.
What case is корзине in and why?
Корзине is in the prepositional case, which you use after the preposition в to indicate location (where something is).
How do you know в here takes the prepositional case and not the accusative?
When в means “into” (movement toward), it takes accusative; when it means “in” or “at” (static location), it takes prepositional. Here we're describing where the vegetables lie, so it's prepositional.
Why is the verb лежат used instead of есть?
Лежать (“to lie”) describes the physical position of objects. Есть is a general existential verb meaning “there is/are.” Using лежат gives a more vivid picture: the cucumbers, tomatoes, and potatoes are actually lying in the basket.
Why are огурцы and помидоры in the plural, but картофель in the singular?
Огурцы and помидоры refer to multiple countable items, so they are in the nominative plural. Картофель is treated as a collective mass noun (potatoes in general), so it remains in the nominative singular.