The Mistress said, "Fanny, did you mail the two letters I gave you yesterday?"
View answer & explanation Ans: The mistress asked Fanny if she had mailed the two letters she had given her the day before.
Correct Answer: The mistress asked Fanny if she had mailed the two letters she had given her the day before.
In indirect speech, 'did you mail' becomes 'had mailed' and 'yesterday' becomes 'the day before', so the mistress asked Fanny if she had mailed the two letters she had given her the day before.