She's middle-aged. 她已到中年了。
A: Your mother is very young.
A: 你的母亲很年轻。
B: No, she's not. She's middle-aged.
B: 不,她不年轻了。她已到中年了。
A: Middle-aged? She's only about 40.
A: 中年?她才40岁上下。
B: 40 is middle-aged. 40 is old!
B: 40岁就是中年。40岁的人老了!
A: 40 is not old! Wait till you're 40.
A: 40并不老!等你到40岁就知道了。
B: I never want to be middle-aged.
B: 我永远也不想到中年。