v.变坚韧；变健壮；变顽固
This experience will toughen her. 这次经历会让他变坚韧。
The company leader said that army life would toughen the recruits up. 连长说军队生活可以使新兵锻炼得更坚强。
All this mountain climbing will toughen the boys up. 这些爬山运动会把孩子们锻炼得身强体壮。
