Lesson 9
Modal Verbs

Modal verbs

Mastering means having full command; that’s much more than just knowing.

In this lesson, we’ll take a look at the modal verbs.

As with the verb tenses we have studied in the previous lessons, you might think that modal verbs are a subject that should already be known by upper intermediate students (if it’s your case). However, this is not always true. Many students have trouble dealing with modal verbs. That’s why it’s important for you to go over this subject. If you think you already know everything there is to know about modal verbs, please concentrate on pronunciation.


The Modal verbs

What are modal verbs?

Modal verbs are a type of auxiliary verbs that change “the mode” (that’s the origin of the word “modal”) of other verbs.

For example, if I say:

- I play football every Saturday.


I can change the “mode” of the verb “to play” by placing a modal verb right before it.

- I must play football every Saturday.

By adding, “must” to the verb “play”, I get a different meaning. In this case, I am indicating that “playing football every Saturday” is an obligation.

How many modal verbs are there?

There are about 10 modal verbs, but grammarians usually add other verbs to the list below because they’re studied alongside with them. We’ll talk about these later.

  1. Can- poder- Example: I can do it. Lo puedo hacer.

  2. Could- pude, podría Example. I could do it.  Lo pude/podría hacer. Note: exact meaning will be given by the context.

  3. Might- puede que, quizás, a lo mejor. Example: He might come. Puede que él venga.

  4. May- puede que. It may rain.

  5. Will- to form the future tenses. Endings –rá- ré in Spanish. Example: I will see it. Lo veré.  Note: The negative form of will is “will not”, but it’s usually expressed as “won’t”

  6. Would- to form the conditional. Endings –ría in Spanish. Example: I would do it.  Yo lo haría.

  7. Must debo. Example: I must work. Yo debo trabajar.

  8. Should- debería- Example: You should come. Tú deberías venir.

  9. Shall- suggestion, invitation and future.  Examples (suggestion): Shall we have a break? ¿Nos tomamos un descanso? – (Future). They shall come. Ellos vendrán.

  10. Ought to- debería. Example: They ought to clean the room.


What do these verbs have in common?

  1. They cannot be conjugated. In other words, you don’t add –s or –es for the third person, and they don’t have a future or past version except insofar as some of them come in present form. For example, “can” is in present while “could” is used in the past.
  2. They can’t be used as infinitives, participles, imperatives or, in some cases, subjunctives.
  3. They function as auxiliary verbs as they modify the meaning of the verbs placed next to them.
  4. It’s not possible to put two modals verbs together. Example: You can’t say: I will can.  INCORRECT.

Semimodals and other verbs

There are other verbs that are not considered, strictly speaking, “modal verbs” but are studied together with modal verbs because they share some characteristics with them (semimodals) or because they are used to replace modal verbs.


  1. Had better: Más vale que
  2. Dare: atreverse
  3. Need: necesitar
  4. Used to: solía, o antes hacía algo que ya no hago.

  • Other verbs that are usually studied together with modal verbs

    Had- Past tense of “have”. It’s studied together with “must” because it is used as its past tense

    • He must study today. Él debe estudiar hoy.
    • He had to study yesterday. Él debió/tuvo que estudiar ayer. Note: I can’t say “He musted studied yesterday”. INCORRECT.

    To be able to- it is studied together with can and could, because we can’t use “can” in future or past tenses.


    • I won’t be able to see you tomorrow.
    • It not possible to say: I won’t can see you tomorrow. INCORRECT.

    In the case of “could”, usually the use of “be able to” in the past is optional although there is a slight difference in meaning. “Be able” means ability, or special skill to do something, like in Spanish “ser capaz”. “Can” or “could” instead don’t have this connotation).

    Example of the use of “be able” and “could” for past tense:

  • I would have been able to work if he had let me. CORRECT – Habría sido capaz de trabajar si él me hubiese dejado.
  • I could have been able to work if he had let me. CORRECT. Podría haber trabajado si él me hubiese dejado.

  • Structure:

    • Affirmative: Subject + modal verb+ main verb + object. Example: We can work harder.
    • Negative: Subject + modal verb+ not + main verb + object. Example: She wouldn’t do something like that.
    • Question: Modal verb+ subject + main verb + object? Example: Could they go home?
    • Negative question: Modal verb + not + subject + main verb + object?  Example: Won’t he come?
    • Answers: Yes, + subject + modal verb- No, +modal verb +not. Example: Yes, I can- No, I can’t.

    Example “Modal verb” audiobook chapter 6: He can’t marry just anyone.