When expressing obligation or necessity in English, we usually use the same phrase “have to” (or “has to”). We would say “I have to go to the store,” and we would say, “In order to be a good singer, one has to practice.” The same verb phrase works for both situations.
In Spanish, however, there are two verb phrases for these separate ways to express obligation.
Tener + que + infinitive
In Spanish, if you are going to name someone specifically and talk about what that person has to do, you will use the verb tener combined with the word "que" (no accent) and a verb in its infinitive (unconjugated) form. In these sentences, the verb tener is conjugated to match the subject of the sentence.
Tengo que lavar el perro. (I have to wash the dog.)
Tienes que leer el libro. (You have to read the book.)
Tenemos que practicar el piano. (We have to practice the piano.)
Hay + que + infinitive
Sometimes you want to talk about something that needs to be done, but without naming a specific person who has to do it. In this case, in English, you might say "one has to …". In Spanish, this is where we use the verb "hay" plus the word "que" (still no accent) and the infinitive form of a verb. This phrase substitutes for "One has to …" or "It is necessary to …" in Spanish.
Hay que llamar por teléfono. (One has to/it is necessary to call on the phone.)
Hay que estudiar mucho. (One has to/it is necessary to study a lot.)
Hay que caminar. (One has to walk/It is necessary to walk.)
Now You Practice
This may be a lesson on learning Spanish for free, but you still have to do some of the work.
Practice using tener + que + infinitive and hay + que + infinitve to describe things that people have to do (or things that are necessary to do).
Download this worksheet to practice translating phrases of necessity and obligation from Spanish to English and from English to Spanish. Page two of the worksheet includes an answer key, so don’t scroll down until you have practiced on your own first.