seventeen 四级六级

At the tender age of seventeen I left home.

早在七岁的小小年纪,我就离开了家。

In an unprecedented action, the army, on its own initiative, arrested seventeen civilians.

军队竟然擅了17 个平民，这种行为简直是前所未有。

What's seventeen plus nine?

17加9等于多少?

He’s only seventeen, but he has an old head on young shoulders and remains calm under pressure.

他只有七岁，不过却少年老成，面对压力沉着冷静。