English Grammar: Mastering Relative Clauses & Modal Verbs

Unit 5: Relative Clauses (Las Oraciones de Relativo)

Defining Relative Clauses

WHO and THAT: Referring to People

  • There are many holidaymakers who/that prefer travelling in their own country.

WHICH and THAT: Referring to Objects/Things

  • Dark tourism is a phenomenon which/that is attracting many people.

WHEN and THAT: Referring to a Moment in Time

  • It was in 1986 when/that the Chernobyl disaster took place.

WHERE: Referring to a Particular Place

  • Many people visit places where tragedies have happened.

WHOSE: Referring to Possession

  • Dr. Barrett is a researcher whose study of dark tourism has just been completed.

Non-Defining Relative Clauses

WHO, WHICH, WHEN, WHERE, WHOSE can all be used, but THAT cannot be used. These clauses are set off by commas and provide additional, non-essential information.

  • In the past, some people, who were rich, used to visit battlefields.
  • This site, where a disaster occurred, has become popular with tourists.

Unit 6: Modal Verbs (Los Modales)

Modal Verb: CAN

  • Ability: You can swim very well.
  • Request: Can you help me wash the car?
  • Possibility: I can lend you my car.
  • Suggestion: You can bring something for my birthday party.

Modal Verb: BE ABLE TO

  • Ability: Don’t worry. I will be able to find the street.

Modal Verb: CAN’T

  • Inability: He is very nervous. He can’t sleep.
  • Prohibition: You can’t eat sweets before dinner.
  • Disbelief: That can’t be your father. He looks very young.

Modal Verb: COULD

  • Past Ability: My mother could dance when she was a child.
  • Polite Request: Could you pass me that book, please?
  • Polite Suggestion: We could visit him next week.
  • Possibility: My sister could come to the party.

Modal Verbs: MAY / MIGHT

  • Possibility: It may/might be a sunny weekend.

Modal Verb: MAY

  • Polite Request: May I borrow your dictionary, please?

Modal Verb: WOULD

  • Formal Request: Would you come with me to the wedding?
  • Offer: Would you like some coffee?

Modal Verb: MUST

  • Obligation, Strong Necessity: She must wear a uniform at her school.
  • Certainty (that something is true): My cousin has broken his leg. It must hurt him very much.

Modal Verb: HAVE TO

  • Obligation, Necessity: You have to study hard if you want to get good marks.

Modal Verb: NEED TO

  • Obligation, Necessity: I need to buy some meat for dinner.

Modal Verb: NEEDN’T

  • Lack of Obligation/Necessity: You needn’t take me home today.

Modal Verb: DON’T HAVE TO

  • Lack of Obligation/Necessity: We don’t have to attend the conference.

Modal Verb: MUSTN’T

  • Prohibition: You mustn’t step on the grass.

Modal Verbs: SHOULD / OUGHT TO

  • Advice, Opinion: She should/ought to tell them the truth.

Perfect Modals (Los Modales Perfectos)

Perfect Modal: MUST HAVE

  • Certainty (that something was true in the past): It must have been very hard for her to hear the truth.

Perfect Modals: MAY / MIGHT HAVE

  • A Guess About a Past Action: She may/might have forgotten about our meeting.

Perfect Modal: COULD HAVE

  • Ability to Do Something in the Past (which in the end was not done): I could have gone with him, but I decided to stay home.

Perfect Modal: COULDN’T HAVE

  • Certainty (that something did not happen in the past): They were really in love with each other. She couldn’t have broken up with him.

Perfect Modal: WOULD HAVE

  • Desire to Do Something in the Past (which in fact could not be done): We would have travelled to the USA, but we didn’t have enough money.

Perfect Modals: SHOULD / OUGHT TO HAVE

  • Criticism or Regret After an Event: You should/ought to have told them we aren’t friends anymore.

Perfect Modal: SHOULDN’T HAVE

  • Criticism or Regret After an Event: We shouldn’t have left before the concert ended.

Perfect Modal: NEEDN’T HAVE

  • An Unnecessary Past Action: I was going to make dinner. You needn’t have made it.