Hiccup knows a lot of languages so, whenever he gets annoyed or frustrated at someone he just talks in another language to irritate them.

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Hiccup groaned in annoyance, glaring at the group in front of him. The twins, as usual, were fighting each other. Snotlout was flirting with Astrid who was twirling her axe in her fingers trying not to attack him. Fishlegs stood awkwardly between the two groups not sure what to do. Hiccup rubbed his head, frustrated.

"Guys" he tried only to be ignored

"Stop it guys!" He shouted again but still all but Fishlegs didn't hear him. This was beginning to frustrate him to no end. Grinning, he had an idea. Taking a deep breath he shouted

"silence!"

All the teens turned to look at him with looks of shock on their faces. "Hiccup what?"

"vous ne seriez pas tranquille."

Hiccup grinned in response Astrid scowled "Hiccup why are you talking another language?"

"c'est amusant"

By this point the twins were looking confusedly at Hiccup and then to each other, trying to figure out what was going on, Fishlegs was looking rather helpless, Snotlout was looking irritated and Astrid was looking a bit murderous. Hiccup was finding it extremely amusing.

"Hiccup" Astrid growled

"quoi?"

"What are you doing Hiccup?" Fishlegs questioned. At that point Gobber walked in. "How are you guys doing?" He greeted walking up to them but stopped as he saw the looks on the groups faces. Glancing at the irritated and confused looking group to a pleased looking Hiccup, Gobber sighed.

"He's started talking in another language hasn't he."

"Yeah he has" Asrtid grumbled, glaring at Hiccup

"How did you know?" Fishlegs asked

"Can you get him to stop? It's irritating." Snotlout said.

Gobber sighed "that's the point." He said "if you annoy him, he'll start talking in another language to annoy you. He's started doing it ever since he began traveling. It angers Stoick to no end." With a triumphant grin, Hiccup stretched "bien… Je dois y aller maintenant"

"What?" Hiccup began walking off "Je vais voler"

"Hiccup!"

"Where are you going?!"

"Hiccup."

"au revoir!"

"Hiccup!"

As Hiccup left, the group could only stare after him. Gobber, seeing Astrid murderous glare, grinned and spoke "Don't worry, he'll be back to speaking normally soon."

"ne comptez pas sur elle!" Was called back.

Astrid growled and chased after him. "Hiccup what did you say! Hiccup! Get back here!"

"jamais!"

Xx-Xx-Xx

Edit- as requested, here are the translations

-vous ne seriez pas tranquille= you wouldn't be quiet

-c'est amusant= it's fun

-quoi?= what?

-bien... Je dois y aller maintenant= well... I need to get going now

-Je vais voler= I'm going flying

-au revoir= bye

-ne comptez pas sur elle!= don't count on it!

-jamais= never