Indirect Speech Exercise:

The teacher asked the boy if he knew Hindi.

Explanation:

To convert direct speech into indirect speech, we follow certain rules.

1. We change the tense of the verb in the reported speech. If the reporting verb is in the past tense, we change the tense of the verb in the reported speech accordingly.

2. We change the pronouns in the reported speech according to the subject of the reporting verb.

3. We change the time and place expressions if necessary.

In the given sentence, the reporting verb 'said' is in the past tense. So, we need to change the sentence into the past tense. The direct question is in the present tense, which needs to be changed into the past tense.

Steps to convert the sentence into indirect speech:

1. The teacher asked (past tense) the boy.
2. The question "Do you know Hindi?" is in the present tense. So, we need to change it into the past tense. "Did you know Hindi?"
3. Combine the two sentences: The teacher asked the boy if he knew Hindi.

Therefore, the indirect speech of the given sentence is "The teacher asked the boy if he knew Hindi."

Conclusion:

In indirect speech, we report what someone said, without using their exact words. We use indirect speech when we want to report what someone said without quoting them directly. It is useful in writing, conversation, and reporting speeches.