Chinese because they can be so direct and all of the words are so short and snappy (and Mandarin has more polysyllabic words than any other dialect!). Want to order something? No need for politeness, just say, "我要 [insert name of what you want here]!" Want to call the waiter over? Just yell, "Eh! 服务员!" (it's a real-life example- my Chinese teacher said exactly that in I think it was Shanghai).