The sturdy box was made of stiff cardboard.

那个结实的盒子是用硬纸板做的。

youdao

If you are planning to mail your portfolio, it is important to package it in a sturdy box.

如果你准备邮寄你的作品集，找个坚固的盒子包装是很重要的。

youdao

Please put her in a nice sturdy box with her journal and bag and send her to Sac City State Bank, attention: Caretaker of Carmen Bear.

请把她连同日志和旅行袋一起放在结实的盒子里，然后寄到萨克市州立银行，收件人：卡门熊的监护人。

youdao

The elephant was given several sticks and a sturdy square box.

WSJ: The Brains of the Animal Kingdom