Esta casa es bonita.
English: This house is beautiful.
Demonstrative adjectives in Spanish are words used before a noun to indicate which person or thing you are talking about, showing how close or far it is from the speaker.
Use these adjectives when you want to point out something specific and show its distance from you: 'este' for something close, 'ese' for something at a medium distance, and 'aquel' for something far away.
Esta casa es bonita.
English: This house is beautiful.
Esos libros son interesantes.
English: Those books are interesting.
Aquella montaña es muy alta.
English: That mountain (over there) is very tall.
Estos zapatos son nuevos.
English: These shoes are new.