english: Now, either we're all just becoming really grumpy as we get older, or it may mean that as you understand laughter better, and you are getting better at doing that, you need more than just hearing people laugh to want to laugh.
non_english: Ofwel we worden chagrijniger  naarmate we ouder worden, of het betekent dat  naarmate je lachen beter begrijpt, je meer nodig hebt om te lachen dan gelach van andere mensen.