Final answer:
The sentence 'This morning the burglar was arrested by the police' can be converted into active voice as 'The police arrested the burglar this morning'.
Step-by-step explanation:
To convert the sentence 'This morning the burglar was arrested by the police' into active voice, you need to change the subject and the verb. In an active voice sentence, the subject is the one who performs the action, rather than the one who is acted upon. Therefore, 'The police arrested the burglar this morning' is the equivalent active voice sentence.
Learn more about Active Voice