Which sentence uses the conditional form of the verb send?

1. I am sending a letter to our grandparents.

2. Send, a letter to our grandparents.

3. I could send a letter to our grandparents.

4. I , suggest you send, a letter to our grandparents.

3. I could send a letter to our grandparents.

The sentence that uses the conditional form of the verb "send" is:

3. I could send a letter to our grandparents.

The sentence that uses the conditional form of the verb send is:

3. I could send a letter to our grandparents.

To identify the conditional form of a verb, we typically look for the use of words like "could," "would," or "should" in the sentence. In this case, the word "could" is present, which indicates a possibility or condition.