The only thing to do was knuckle down and get on with some serious hard work.唯一要做的事就是开始努力工作, 干些正经事。

He managed to knuckle down to his lessons long enough to pass his examination.他设法多花些时间做功课, 通过了考试。

Carol knuckled down to her task.卡罗尔开始认真完成她的任务。