新买的登山鞋比旧的那双更结实耐穿。

The new hiking boots are ___tougher than the old pair.

这次的面试问题比上次更加棘手。

The interview questions were ___tougher this time compared to last.

学校对手机使用制定了更严格的规定。

The school has implemented ___tougher rules on mobile phone usage.

经历困难后，她变得更坚强了。

After facing hardships, she became ___tougher.