В магазине лежали кекс с изюмом, рулет с яблоком и торт с белой глазурью.

In the shop there were a raisin cake, an apple roll, and a cake with white icing.

Breakdown of В магазине лежали кекс с изюмом, рулет с яблоком и торт с белой глазурью.

• белый: white
• яблоко: the apple
• с: with
• в: in

Questions & Answers about В магазине лежали кекс с изюмом, рулет с яблоком и торт с белой глазурью.

Why is в магазине in that form?

Because after в meaning in, Russian uses the prepositional case for location.

• магазин = store, shop
• в магазине = in the store

So this is a standard location pattern:

• в доме = in the house
• в школе = at school
• в магазине = in the store

If в meant motion into, you would usually see the accusative instead.

Why is the verb лежали plural?

Because the subject is really a list of three things:

• кекс с изюмом
• рулет с яблоком
• торт с белой глазурью

Each noun is singular by itself, but together they form a plural subject, so the verb is plural:

• лежали = they were lying / were sitting / were there laid out

If there were only one item, you would use singular, for example:

• В магазине лежал кекс с изюмом.

Why does the sentence use лежали instead of были?