Completing the sentences with the correct grammatical words is as follows:
6. We must study hard <u>A. for</u> the exam.
7. We must study hard <u>D. to</u> prepare for the exam.
8. Why you are very happy today? <u>A. I know</u> it's your birthday.
9. <u>D. I am going to study</u> hard for our next text.
10. If I could <u>C. be</u> an animal, I <u>D. would be</u> a lion.
<h3>What are parts of speech?</h3>
Correct grammatical words use the right parts of speech to fit the grammatical context.
The parts of speech in English grammar include:
- Noun
- Pronoun
- Adjective
- Verb
- Adverb
- Preposition
- Conjunction
- Interjection.
For example, it is not correct grammar to use a wrong preposition, e.g. "of" when "for" should be used.
Thus, the sentences have been completed with the correct grammatical words.
Learn more about parts of speech at brainly.com/question/721326
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