Who said "I won't give up, and I won't let others give up either."?

This quote is attributed to Captain America (Age of Ultron).

I won't give up, and I won't let others give up either. - Captain America (Age of Ultron)

"I won't give up, and I won't let others give up either."

Captain America (Age of Ultron) Perseverance

"I'm always angry."

"The world is in our hands now."

"We may not be able to save everyone, but we have to try."

"I can do this all day."

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."