Question

The old man failed to recall certain incidents from his school days. (change into negative)​

Answer 1

Answer:

The old man failed to recall certain incidents from his schools days. This is assertive sentence. So change in into negative.

Negative form of this sentence will be :

The old man did not failed to recall certain incidents from his school days.

Explanation:

Hope it helps :-)

Answer 2

Answer:

The old man did not failed to recall certain incidents from his school days.

Explanation:

hope it helps you