To describe where things are located in your environment at home using the phrases "al lado de", "encima de", "detras de", and "delante de", and the Spanish word "Hay" (which means "there is/are"), you can use the following examples:
1. Hay una mesa al lado del sofá. - There is a table next to the sofa.
To find out where things are located in your environment at home, look around and identify the objects you want to describe. In this case, find a table and the sofa. Then, by observing their positions, you can say that the table is "al lado de" (next to) the sofa.
2. Hay un libro encima de la mesa. - There is a book on top of the table.
Look for a book and a table in your environment at home. Then, observe their positions relative to each other. If the book is placed on top of the table, you can use the phrase "encima de" (on top of) to describe their location.
3. Hay una silla detrás del escritorio. - There is a chair behind the desk.
Find a chair and a desk in your environment at home. By observing their positions, if the chair is located at the back of the desk, you can use the phrase "detrás de" (behind) to describe their location.
Remember to substitute the definite articles "la" or "el" with "le" or "del" when the objects being referred to are mentioned again in the same sentence.