laborious相关的词根或词缀是: labor

But conventional cross-breeding is costly and laborious for grapes .

但是传统的葡萄杂交非常费时费力且价格昂贵。

Registration is laborious and time-consuming , and would discourage the use of over-the-counter derivatives .

登记是一项费时费力的工作，将会打击人们使用场外衍生品交易的积极性。

It takes 56 laborious steps to set up a business .

要开业做生意需要通过56步吃力的手续。

Hours after they finished the test on monday , both students had collected the answers from the district education bureau and begun the laborious process , with the help of their teachers , of estimating their scores .

周一高考结束才几个小时，他们两个就在当地教育局拿到了试题答案，在老师的帮助下开始了艰苦的估分过程。

That is a bit too laborious .

这有点过于费力了。