This ancient proverb, 'know the other side and yourself, and you will not be in danger in a hundred battles', teaches us the importance of understanding ourselves and others.

He solved the problem using that technique.

He is learning the art of painting.

He defeated the enemy using that technique.

She is planning a date with her current boyfriend.

He lost everything.

My boyfriend gave me a gift.

Everyone was surprised by the news.

He knows that pain through his own experience.

He is feigning ignorance about that problem.