There are several different ways to express obligations and responsibilities the things you need or have to do in Spanish. These activities may range from studying for an exam to washing your car to returning books to the library.
The first two expressions you will learn are fixed, impersonal expressions that do not change. All you do is add an infinitive to show exactly what it is that it is necessary to do.
| es necesario/hay que + | infinitivo |
|---|---|
 Es necesario |
estudiar para los exámenes. |
| Hay que |
sacar la basura cada dos días.  |
The next set of expressions that you will learn involve verbs that you will conjugate according to the person or people who need or should do something, then add an infinitive. You will notice that one of these forms uses the verb tener, which you have already seen many times throughout this course. You will add que after the conjugated form of tener to mean “to have to.”
| necesitar/tener que/deber + | infinitivo |
|---|---|
| Necesito |
llamar a mi mamá esta semana. |
| Juan debe |
hacer más ejercicio. |
| Nosotros tenemos que |
limpiar la casa hoy. |
| Los estudiantes tienen que |
hacer la tarea para sacar buenas notas. |
| Marlene y José deben |
tener un poco más cuidado. |
| Vanesa y yo debemos |
estudiar más. |
| Joaquín tiene que |
ir al médico.  |
| Ustedes necesitan |
descansar. |
| Tenemos que |
llegar al aeropuerto a tiempo. |
