Chris Hemsworth has to ''pretend'' to understand his wife when she tells their children off in Spanish.

The 'Avengers: Infinity War' actor has been married to Elsa Pataky for over seven years but still doesn't understand her native language, though their three children, six-year-old India and four-year-old twins Sasha and Tristan, are fluent speakers.

He said: ''They're fluent in Spanish. I speak one sentence.

''I pretend to [understand] my wife will tell them off and it sounds like 'dghdghdgh' to my ear and I'm like, 'That's right... what did you tell them?'

''You'd think [it would be easy to learn]. When I hear the Spanish directed at me it's usually in pretty unfortunate, controversial, aggressive situations so I'm just thinking, 'What is she saying right now and what's my comeback?' When we're fighting basically. Which is never...''

While Elsa has been teaching their brood her language, Chris, 34, has been spending time teaching the kids how to surf.

After talk show host Ellen Degeneres shared a video clip of him riding the waves with his daughter on his back, he said: ''I occasionally get back problems and since I've started doing that it's got worse, 20lbs of extra weight and you're getting choked out. I didn't think it would stick but they're like, 'More, more, more.'

''They surf, tiny little waves. Big surfboards make it easy. They love it and where we live is perfect to do that, they're water babies.''

Meanwhile, Elsa, 41, has previously praised Chris for being a great father who has never made their family feel like his work comes first, even though things were ''difficult'' when they had India just as his career was taking off.

She said recently: ''I think any time you start a family without knowing each other that much, it can be complicated.

''He was very young to be starting a family, and at the same time he was juggling that with his career and it was sometimes difficult, there was so much going on.

''But he was always trying to be the best dad and has never failed to make me feel like his family is the most important thing to him and [going through that] is how we've become so strong together.''