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Class 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.The rule is printed on the ticket and there is no way round it. Which sentence fits?

    • a) Passengers might carry their tickets.
    • b) Passengers must carry their tickets.
    • c) Passengers should carry their tickets.
    • d) Passengers ought to carry their tickets.

  2. 2."Must" has no past form, so a sentence about yesterday needs a different verb. Yesterday I ____ stay back and finish the work.

    • a) must have
    • b) must
    • c) had to
    • d) have to

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

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

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

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

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

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

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

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

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

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

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

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

  1. 1. b) Passengers must carry their tickets.
  2. 2. c) had to
  3. 3. d) You ought to see a doctor.
  4. 4. 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
  5. 5. c) They cannot be inside.
  6. 6. d) She cannot be the new librarian.
  7. 7. must
  8. 8.
    • do not have to
    • don't have to
    • need not
    • needn't
    • do not need to
    • don't need to