PASO 1Elige la opción correcta
PASO 2Agrega los ejercicios que te gustan a Favoritas
As a rule, verbs denoting a state rather than an act have no continuous forms, like understand, know, believe, like, love, belong, prefer, consist, mean, hear, see, etc.
The infinitive simply names an action without reference to person, number or time. Therefore, it can't make sense without the help of a finite verb
Don't use the past perfect unless there is another verb in the past tense in the same sentence.