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Year 8 English — Modals of obligation and probability

Say how strong an obligation is with must, have to, should and ought to, and say how sure you are with must, might and cannot.

Name: ________________________

  1. 1.Write the one word that shows the speaker is certain: "Ravi's bag is here but his shoes are gone, so he ____ be outside."

  2. 2.Which sentence says the speaker is certain that something is NOT true?

    • a) She must be the new librarian.
    • b) She cannot be the new librarian.
    • c) She might be the new librarian.
    • d) She should be the new librarian.

  3. 3.Sort each sentence by what its modal verb is doing.

    Groups: Says there is no choice · Gives advice

    • Every rider must wear a helmet.
    • I think you should ask your teacher first.
    • You ought to apologise to her.
    • Visitors have to sign the register at the gate.
    • Passengers must show their tickets to the guard.
    • You should get more sleep before the exam.

  4. 4.Which sentence gives advice in the mildest way?

    • a) You cannot see a doctor.
    • b) You have to see a doctor.
    • c) You ought to see a doctor.
    • d) You must see a doctor.

  5. 5.Sort each sentence by whether it forbids something or simply says it is not necessary.

    Groups: Forbids it · Says it is not necessary

    • Players do not have to bring their own bats.
    • You must not open that door.
    • You do not have to open that door.
    • Players must not argue with the umpire.

  6. 6.The classroom lights are off and the door is locked. Where is the class?

    • a) They cannot be inside.
    • b) They have to be inside.
    • c) They must be inside.
    • d) They should be inside.

  7. 7.Fill the gap so that the sentence means there is no need at all: "There is plenty of time — we ____ leave before six."

  8. 8.Sort each sentence by how sure the speaker is.

    Groups: Sure it is true · Not sure either way · Sure it is not true

    • That cannot be Ravi — he left for Delhi last week.
    • She could still be on the earlier bus.
    • He might be waiting at the other gate.
    • Her bag is here, so she must be inside.
    • The lights are on, so somebody must be at home.
    • It cannot be six already; the bell has not rung.

Answer key — Year 8 English — Modals of obligation and probability

  1. 1. must
  2. 2. b) She cannot be the new librarian.
  3. 3. Every rider must wear a helmet. → Says there is no choice; You should get more sleep before the exam. → Gives advice; Visitors have to sign the register at the gate. → Says there is no choice; You ought to apologise to her. → Gives advice; Passengers must show their tickets to the guard. → Says there is no choice; I think you should ask your teacher first. → Gives advice
  4. 4. c) You ought to see a doctor.
  5. 5. You must not open that door. → Forbids it; You do not have to open that door. → Says it is not necessary; Players must not argue with the umpire. → Forbids it; Players do not have to bring their own bats. → Says it is not necessary
  6. 6. a) They cannot be inside.
  7. 7.
    • do not have to
    • don't have to
    • need not
    • needn't
    • do not need to
    • don't need to
  8. 8. Her bag is here, so she must be inside. → Sure it is true; The lights are on, so somebody must be at home. → Sure it is true; He might be waiting at the other gate. → Not sure either way; She could still be on the earlier bus. → Not sure either way; That cannot be Ravi — he left for Delhi last week. → Sure it is not true; It cannot be six already; the bell has not rung. → Sure it is not true