Four relationship tips from psychologists who have counseled 40,000 couples.

John and Julie Gottman, renowned psychologists, have interviewed 40,000 couples to determine what makes love endure. Their research at The Gottman Institute has revealed how successful relationships navigate conflict and express affection.

Here are four things that people in long-lasting partnerships do:

1. Fight to understand.

According to data from The Gottman Institute, over 69% of conflicts in relationships are chronic, meaning they persist indefinitely.

By studying, they discovered that a recurring fight doesn't always have to be harmful. In fact, any relationship conflict can be managed effectively with the right fighting techniques.

"What is the biggest mistake that disasters of relationships make when it comes to fighting right, whether it's a perpetual problem or a solvable one? John Gottman said at a TED Talk in April. The answer is that they fight to win, which means someone has to lose. Instead, the masters do not fight to win but to understand."

It's unlikely that you'll be able to reach a resolution if you're fighting to prove a point and not to understand the other person's perspective, as the other person will be seen as the enemy.

Instead of asking "Why did you come to that conclusion?" try asking "Can you tell me more about the factors that led you to that conclusion?" This shows empathy and allows for a more open and honest conversation.

2. Make repairs.

According to an interview with psychotherapist and bestselling author Esther Perel, the Gottmans identified a common trait among successful couples: their ability to perform "repairs."

"Julie Gottman told Perel that they made repairs when their partner didn't receive a bid for connection, and also if they said or blurted out the wrong thing."

Repairing a relationship doesn't require expensive gestures or gifts. It can be as simple as acknowledging your partner's humanity and having an open conversation.

John Gottman recounts an instance from one of his clients who recently had a disagreement with their partner, saying, "One man remarked, 'Now that we've ruined our personalities, let's enjoy some cheesecake.'"

3. Express positivity.

Gottman's research shows that successful couples have a ratio of five positive to one negative interactions during conflicts.

During a longitudinal study, couples were asked to resolve a disagreement in 15 minutes. The researchers recorded the conflict, watched the tapes, and categorized each interaction as positive or negative.

Positive interactions involved smiling, touching the other person's hand, or expressing understanding, while negative interactions involved insulting or blaming the other person.

"In their book "The Love Prescription: 7 Days to More Intimacy, Connection, and Joy," they documented the behavior of couples, collected data, and then released them back into the wild."

"Six years after our initial follow-up, we discovered that the couples who had maintained a five-to-one ratio or more during conflicts were still together and in love."

4. Say 'thank you.'

You may not frequently express gratitude to your partner compared to other individuals in your life, such as your barista, colleagues, and a stranger who held the door open for you.

According to the Gottmans, a successful relationship involves a culture of appreciation, where we are skilled at recognizing both our partners' strengths and weaknesses.

The Gottmans suggest expressing gratitude for the chore done by your partner, even if it's just a simple thank you.

I appreciate it when you take out the trash every night, as it allows me to wake up to a clean kitchen.

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