MELBOURNE, Australia (AP)—Tell Roger Federer a joke in French, and he might not laugh as he would if it were told in English. Or Swiss German, for that matter.

Tennis’ multilingual maestro says his sense of humor is different, depending on what gear his mind is running in at the time.

The 16-time Grand Slam champion is fluent in English, French, German and Swiss German, the distinctly different version of the Germanic lingo spoken in his homeland. Add into the mix some South African blood on his mother’s side and Federer appears a bit like a one-man United Nations.

The downside is that after each match, the 29-year-old Swiss appears at news conferences where he is asked in English to talk about his game, rivals, standings and prospects for becoming the greatest tennis player ever. Then he does it again in French. Then German. And so on …

“Sometimes I wish I never told anybody I learned French,” Federer said Tuesday, quickly adding that he’s proud to have learned the language along with the others because it gives him a chance to relate to more people.

He said it’s all part of “what I have to do in the tennis world.”

“That it comes at a cost, sure, but I don’t mind it. I try to have fun with it,” he said during his news conference after beating countryman Stanislas Wawrinka 6-1, 6-3, 6-3 to reach his eighth consecutive Australian Open semifinal.

“I have almost, I don’t want to say characters, but I have different humor in all the different languages, which is kind of fun for me, too,” he said. “Getting to know myself through different languages is actually quite interesting for me.”

One language Federer does not speak is Spanish, the native tongue of Rafael Nadal. The top two players in men’s tennis are on track to meet Sunday in their eighth Grand Slam final.

Federer said the two have become friendlier over the years. While they don’t exactly hang out together, they chat and regularly see each other.

“We talk about many things, but tennis probably being one of them at times, yeah,” Federer said.

Doubling Up: Flavia Pennetta is using her exit from the singles draw of the Australian Open as inspiration in doubles.

Pennetta and Argentinian partner Gisela Dulko are the top seeds in the doubles and defeated South Africa’s Natalie Grandin and Vladimira Uhlirova of the Czech Republic 6-0, 6-3 Tuesday to reach the semifinals.

That match came a day after her fourth-round defeat to Petra Kvitova in the singles, which kept her from her third Grand Slam quarterfinal.

“Sometimes it is not easy to get back up after a loss in the singles, because you are angry and you really do not want to touch the racket,” Pennetta wrote in a newspaper column.

She does it out of loyalty to her friend, she said, and because it’s fun.

“But I can see why the top-ranking men tend not to play doubles,” Pennetta wrote. “Playing five sets is completely different to the women’s game. It is like another sport and I can understand if they have just completed a five-setter then they may think it is better to use the next day for recovery rather than play doubles.”

Many of the top women play both in many tournaments, including Grand Slams. Both men and women play best of three in the doubles. Most men in the top 10 rarely play doubles at the majors.

Australian D’oh-Pen: Homer Simpson is on the tennis tour, and getting some serious backstage access.

The renowned coach potato—or at least a small plastic representation of him—is popping up all over Melbourne Park, thanks to the joke Stanislas Wawrinka is playing with a friend. Wawrinka, who lost an all-Swiss quarterfinal to Roger Federer, is taking snapshots of the toy and posting them as links to his Twitter feed.

There’s Homer, munching on a doughnut, standing between some fried eggs and tomatoes in the middle of Wawrinka’s breakfast plate. Then he’s teetering on the peak of Federer’s cap—two days before their singles matchup.

“It’s a joke with a friend from the beginning of the year,” Wawrinka said. “I’m doing some picture for Twitter, and all the fans are asking about some more.”