The verb gustar (conjugation) means "to like". Gustar is similar to a reflexive verb, and it is most frequently used in the third person singular or plural. It is always accompanied by (IOP) indirect object pronouns (me, te, le, nos, os, les).

Singular
Me gusta el libro.
      I like the book.

A él le gusta el libro.
      He likes the book.

A ellas les gusta el carro.
      They like the car.

A mí me gusta la casa.
      I like the house.

Plural
Me gustan los libros.
      I like the books.

A él le gustan los libros.
      He likes the books.

A ellas les gustan los carros.
      They like the cars.

A mí me gustan las casas.
      I like the houses.