1. With regular verbs: Usually, adverbs of certainty appear before the main verb in a sentence.
2. With “Be” form verbs: If there is a “be” form verb, then the adverbs of certainty appear after the “be” form verb.
3. With auxiliary verbs: When there is an auxiliary or helping verb in a sentence, the adverb of certainty is placed between the auxiliary verb and the main verb.
4. At the beginning of the sentence: Adverbs of certainty can also be placed at the beginning of the sentence sometimes.
Some more examples:
1. John will probably leave India by tonight.
2. She is definitely the brightest child in her class.
3. Undoubtedly, Shane Watson is one of the greatest cricket players in Australia.
4. Emma is certainly going to visit her friend in Alaska next year.
5. He surely knows how to attract the attention of the customer.
6. David will mostly drink juice during exercise.
7. Glen is probably taking part in the dance competition this month.
8. Eva certainly loves to eat ice cream than fast foods.
9. Clearly, this is an open and shut case of crime with the criminal leaving so many clues behind.
10. Annette has certainly spent much of her time in decorating the room for the party.
11. Probably, we will have lunch at a hotel.
12. Paul is undoubtedly the best singer in his troupe.