Having become one of the world's best players under United boss Sir Alex Ferguson, Ronaldo believes the new wave of Old Trafford's rising stars, such as striker Javier Hernandez and defender Chris Smalling, can also hit the heights.
He told the Mirror: "They must be professional. They must listen to people more experienced than themselves because they are young and they don't always know what is best in a match situation.
"I say, 'Work hard, be professional, respect your coach, your team-mates and respect your opponent.' These are the best qualities for a player to possess."