He restocked the wine rack, replaced the bulb in the bathroom and even refuelled your hatchback. Did you, um, say anything?

A new study from Florida State University, US, shows that acknowledging your partner’s little acts of generosity has a major pay-off. “Expressing gratitude transforms your impression of the other person,” says lead researcher and psychologist Dr Nathaniel Lambert. “It helps people hold each other in higher regard, making them more comfortable when they have to work through bigger relationship issues.” Here's how to express your gratitude the right way.

Random act of kindness: He whips up dinner (no questions asked) after you’ve had a hellish day

What he’s telling you Job stress can cause significant rifts in a relationship and even lead to divorce, found a study at the University of California, US. “Eventually, work anxiety is going to spill over into your relationship,” says psychologist Dr Leslie Becker-Phelps. “Treating you to dinner is his attempt to show you that he’s your teammate in getting through this.”

Be grateful Do you really want to spend your non-working hours stewing about your boss’ behaviour? Well, maybe. But steaming over a work issue will leave a bad taste in your mouth.

“Get away from the negativity by asking his advice,” suggests Dr Becker-Phelps. Every bloke likes giving input, and it allows you to focus on a solution instead of worrying over the problem. Once you’ve got his two cents worth, move on so you can decompress together and enjoy the rest of your meal.

Random act of kindness: He cleaned the house and restocked the fridge (and you didn’t have to ask)

What he’s telling you When your partner gets all domestic on you, it’s probably not because he couldn’t stand the dust on the bookshelves for another minute. He’s doing this just for you – and in a lot of ways, it’s a bigger treat than something he’d pick up at the shopping centre. Seriously.

Be grateful Plenty of men assume gifts are things that come with price tags. So if having someone else do the washing, change the sheets, vacuum the living room and shop for groceries means more than Bradley Cooper rocking up on your doorstep, let him know.

What not to say: “Wow, this is great! Oops, I think you missed a spot…” says Dr Becker-Phelps. If you want this to go from a one-off gesture to routine relationship practice, you need to give him some credit, and leave it at that. “The minute it turns critical, you’ve turned it from a gift into a chore, and he’ll be less likely to do it again,” says Dr Becker-Phelps

Random act of kindness: Flowers! And it’s not even your birthday

What he’s telling you Assuming he’s not trying to get out of the doghouse, a just-because bouquet is a sign he’s committed. “When your partner goes out of his way to surprise you with a gift, he’s sending a message that he’s invested in your happiness,” says Dr Lambert. “Think of these thoughtful acts as deposits in an emotional savings account. The accumulation of small acts over time will earn a huge windfall for your relationship.”

Be grateful Your inclination may be to return the favour, but don’t do it. “Responding to a gift with a gift can backfire,” says psychologist Dr Jeffrey Froh. “It will make him feel indebted to you – and people dislike feeling indebted.” Plus you may come off as a one-upper.

Be appreciative, plain and simple. Place the flowers in a prominent spot and tell him how surprised you are (that’s the reaction he was going for) and how much you love the idea that he was thinking about you. Then wait a day and say it again. “Frequency in expressing gratitude is more important than intensity,” says Dr Froh.

Random act of kindness: He skipped drinks with his friends to go to your niece’s Christmas concert

What he’s telling you When your partner gives up a mates’ date to work around your schedule, he’s making a sacrifice in the name of your happiness. We know, right? Good man. “Men do this as an opportunity to show their love,” says Dr Charles Shelton, author of The Gratitude Factor.

“He is inconveniencing himself to make your life better.” Even the best relationships require sacrifice, and seemingly tiny ones like this also count, says Dr Shelton. “Taking gestures like this for granted can quickly cause tension.”

Be grateful OK sister, it’s all about the delivery here. “The big thing is acknowledging this is not required relationship behaviour,” says Dr Becker-Phelps. He had plans, and he broke them for yours. Granted, that’s what people in committed relationships do for each other, but a simple “I owe you one” conveys that you know the effort he went to. And it wouldn’t hurt to give him some public recognition so he (along with everyone else within earshot) knows just how awesome you think he is.

Wise words: How to double the joy' People who express gratitude more than double their chances of being on the receiving end of that generosity again, a study in the Journal of Personality and Social Psychology'' has found. “There aren’t many things in relationships as equally beneficial to the giver and receiver,” says psychologist Dr Nathaniel Lambert. So pay attention: look for opportunities to be grateful so you can reap this relationship bounty.

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