“Smile, it is the key that fits the lock of everyone's heart”
“Smile is the key that fits to the lock of everybody's heart.”
“A woman should be mindful that the key to one man's heart does not necessarily fits into the lock of another.”
“Jealousy is the lock that closes your heart, understanding is the key that opens it.”
“Don't simply knock and wait for the door to be opened. Go look for the keys. Some fit the lock better than others.”
“This is your heart. Keep it locked until the chap turns up who has the key.”