他年轻吗？不，他不年轻，他老了。

Is he ___young? No, he isn't. He's old.

他太年轻了，还不能独自旅行。

He is too ___young to travel alone.

我爷爷虽然年纪大了，但心态很年轻。

My grandpa is old, but he has a ___young heart.