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Modal Verbs Certainty Practice

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Modal Verbs Certainty Practice

Modal verbs and certainty adverbs show how sure or forceful a statement is. For open-ended rewrites, several answers are possible; sample answers are provided in the answer key.

Match certainty levels

Match each sentence to the certainty level that best fits its wording. Use each level once.

1.Match each sentence to one level: 100% certain, 90% very likely, 70% probable, 50% possible, or 30% unlikely.

A. The gate is certainly locked after the caretaker leaves.
B. It might drizzle during the afternoon walk.
C. The team will probably finish setting up before lunch.
D. It is unlikely that you will try the new art club next term.
E. The bus should arrive before the bell.

50% possible
90% very likely
30% unlikely
100% certain
70% probable

Spot the words

A modal verb often comes before the main verb. A certainty adverb changes how sure a statement sounds.

2.In “Visitors must certainly leave the nature centre by closing time,” identify the modal verb and the certainty adverb.

3.In “We may perhaps need another tray for the seedlings,” identify the modal verb and the certainty adverb.

4.In “The visitors should probably arrive before the show begins,” identify the modal verb and the certainty adverb.

Choose a suitable modal verb

Select the option that best fits the clue in each sentence.

5.The sky is cloudy, but the forecast is uncertain. It ______ rain this evening.

must
might
will

6.The class has a safety rule to follow before using the tools. Students ______ put on safety glasses first.

could
should
might

Adjust the certainty

Rewrite each sentence as instructed. Use a modal verb or certainty adverb to change its force.

7.Make this rule sound less forceful: “All players must return the sports gear before recess ends.”

8.Make this prediction less certain: “The outdoor concert is certain to go ahead on Saturday.”

9.Make this suggestion sound more certain: “You might pack a hat for the hike.”

10.Make this possibility sound more certain: “The choir may perform at the assembly.”

Change one word

Replace exactly one word in each sentence to change its certainty. Then explain the change in meaning.

11.Change one word in “You must stack the chairs before leaving” to make it less forceful. Write the new sentence and explain the change.

12.Change one word in “The museum will certainly open at ten” to make the statement less certain. Write the new sentence and explain the change.

13.Change one word in “You might need a torch for the cave tour” to make the possibility more likely. Write the new sentence and explain the change.

Complete each sentence

Choose a suitable word or words from this bank: must, might, should, could, will, definitely, probably, possibly, certainly, maybe. Some answers may vary; use the context to guide your choice.

14.For safety, visitors stay behind the barrier while the keeper feeds the crocodiles.

15.The school fete be postponed if the storm gets worse.

16.The band sounded fantastic, so I enjoy the concert tonight.

17.If assignments are handed in after the due date, they receive a penalty according to the class policy.

18.The coach has confirmed the match is scheduled, so it begin at 3.30 pm.

Think about certainty

Use complete sentences to explain how word choice affects meaning and tone.

19.How does changing a modal verb or certainty adverb affect the way a sentence sounds? Give an example using the same basic idea with two different certainty levels.

20.Why might a writer choose a softer or stronger expression? Give an example of each and explain when it could be useful.

21.Write one sentence containing a modal verb and a certainty adverb. Then rewrite it with a different certainty level and explain how its meaning changes.