Generally speaking, joy (express) by laughter. But as it turns out, it reveals a lot more than the fact you are happy. It enables listeners, even those who cannot observe you, (realize) if you are having a good time with a close friend or laughing (polite) with a complete stranger.
At least, this is the conclusion (reach) by a team of scientists led by Greg Bryant, assistant professor of Communication Studies at the University of California, Los Angeles. The researchers began by (request) volunteers from across the world to send them audio clips(音频剪辑) of people laughing. The 48 tapes they received (range) from recent recordings of laughter between two college friends ones from conversations made ten years ago. The clips also had all possible (combine)--communications between friends, strangers, all-male groups, all-female groups, etc.
Bryan says that the results of this cross-cultural examination show that people all over the world know laughter in similar ways.
