Answer:
1. Last year, I <u>participated</u> in three sports.
2. Since I <u>am</u> a senior, I <u>think</u> that I <u>will specialize</u> this year.
3. My friends all have jobs, so I <u>am applying</u> at Sonic this year.
4. My parents <u>celebrated</u> when I <u>told</u> them my plans.
5. I <u>can save</u> money for my college expenses.
6. Jeremy <u>will open</u> his own welding business in the next two years.
7. I once <u>thought</u> that I <u>wanted</u> to <u>be</u> a lawyer, but now I <u>am</u> not so sure.
8. My math grades <u>have</u> all <u>been</u> very good, but my English grade <u>could be</u> better.
9. <em> </em>I <u>am thinking</u> that I <u>will explore</u> the field of engineering.
10. When I <u>know</u> what I <u>want</u> to <u>pursue</u> as a career, I <u>will be able</u> to <u>choose</u> a college.
Explanation:
A verb is a word used to describe an action, state, or occurrence, and forming the main part of the predicate of a sentence. Verbs are words that express an action or state of being in a sentence, and a verb describes what the subject of a sentence is doing.