Here is the sentence:
Because Tran knew that a strong chemistry
background was essential for a future pharmacist, she
rose from her warm bed and
begun studying her notes for another test.
The third verb, begun, is incorrect. As you know, this sentence requires the simple past. Began is the right form.
| Verb | Simple Present | Simple Past | Past Participle |
| begin | begin(s) | began | begun |
Go to the next sentence, champ!