It’s common for English language learners to overuse certain modals (e.g., can, etc.) and certain modals can unintentionally lead to over hedging (See Boosting vs. Hedging.)

Benjamin L. Stewart

Modal verbs are auxiliary verbs that express necessity, possibility, permission, ability, probability, or obligation. In English, the primary modal verbs are:

1. Can / Could:
   1. Use for Ability: “She can speak four languages.”
   1. Possibility: “It could rain today.”
   1. Request or Permission (especially Could): “Could I borrow your book?”
2. May / Might:
   1. Permission (more formal than Can): “May I leave the room?”
   1. Possibility or Probability: “She might come to the party.”
3. Will / Would:
   1. Future Actions (Will): “I will go to the store later.”
   1. Polite Requests or Offers (Would): “Would you like some coffee?”
   1. Hypothetical Situations (Would): “I would travel more if I had more time.”
4. Shall:
   1. Formal Suggestion or Offer (mainly British English): “Shall we dance?”
   1. Future Actions (formal): “Shall I open the window?”
5. Should / Ought to:
   1. Advice or Recommendation: “You should see a doctor.”
   1. Expectation: “He ought to be here by now.”
6. Must:
   1. Obligation or Necessity: “You must stop at a red light.”
   1. Strong Recommendation: “You must visit the new museum.”
   1. Logical Assumption: “He must be tired after the long journey.”
7. Dare:
   1. Challenge or Bravery (less common): “Dare she speak out?”
8. Need (Semi-modal):
   1. Necessity (in questions and negatives): “Need I say more?”
9. Used to:
   1. Past Habit or State (not a modal in the traditional sense, but functions similarly): “I used to play basketball.”

Usage Guidelines

• Modals do not change form according to the subject. For example, “She can,” “They can.”
• After a modal verb, the base form of the verb is used: “She can speak,” not “She can speaks.”
• Modals do not have all tense forms, such as past or future. Some have past forms (like “Could” as the past of “Can”) or use other modals for different tenses.
• Negative forms are made by adding “not” after the modal: “She cannot (can’t) speak French.”

Important Points

• The use of some modals can vary in formality. For example, “Shall” and “May” are more formal.
• The choice of modal can subtly change the meaning of a sentence, especially in terms of politeness, certainty, and formality.
• “Will” and “Would” are often used to create conditional sentences.
• Modals are a key component of English language fluency, and understanding their nuances is crucial for effective communication.

Periphrastic modals

Periphrastic modals or modal-like expressions (i.e., phrasal modals) are phrases that function similarly to modal verbs, often expressing similar ideas of possibility, probability, permission, obligation, or advice. Here are some common periphrastic modals along with their uses:

1. Be able to (Ability):
   1. Used similarly to “can” or “could” for expressing ability.
   1. Example: “She will be able to complete the project on time.”
2. Be supposed to (Expectation or Obligation):
   1. Indicates something that is planned or expected.
   1. Example: “He is supposed to arrive at 10 AM.”
3. Be going to (Future Intent):
   1. Indicates a future action or event.
   1. Example: “They are going to launch the new product next month.”
4. Have to / Have got to (Necessity or Obligation):
   1. Used to express a strong necessity or obligation.
   1. Example: “I have to finish this report by tomorrow.”
5. Ought to (Advice, Suggestion):
   1. Similar to “should,” often used for advice or suggestion.
   1. Example: “You ought to check the oil level in your car.”
6. Be allowed to (Permission):
   1. Used to talk about permission.
   1. Example: “Children are not allowed to watch this movie.”
7. Would rather / Would sooner (Preference):
   1. Indicates a preference.
   1. Example: “I would rather walk than drive
8. Be bound to (Certainty):
   1. Indicates that something is very likely or certain.
   1. Example: “She’s working hard; she’s bound to succeed.”
9. Be to (Formal Instruction or Plan):
   1. Used for formal instructions or plans.
   1. Example: “The meeting is to be held on Thursday.”
10. Used to (Past Habit):
    1. Expresses habits or states in the past.
    1. Example: “I used to go jogging every morning.”
11. Be about to (Immediate Future):
    1. Indicates something is going to happen very soon.
    1. Example: “The concert is about to start.”
12. Had better (Advice with Warning):
    1. Suggests advice or recommendation, often with a warning of consequences.
    1. Example: “You had better leave now, or you’ll miss your flight.”

Usage Guidelines

• Like single-word modals, phrasal modals modify the main verb and express modality.
• They often provide nuances or aspects of modality that single-word modals cannot express.
• Some of these expressions are more formal or more specific in their usage.
• They can offer alternatives in contexts where a modal verb’s tense or form limitation is an issue.

Understanding phrasal modals enriches communication, allowing for more precise expression of modality, especially in more complex or formal contexts.