no one–Alicia keys:It's never too late to mend.这句话怎么解释?

It's never too old to learn.怎么解释？ It's never too late to mend.这句话怎么解释? Please say something about"It's never too late for succession" It's never crowded,--------? It's also fun too. It's too hard to me. 翻译: it's now or never it"s too hard It's too hard.Why____the farmer for help. It's too hot.Would you mind ____the door?---____.Please do it now