Arduous: involving a lot of effort and energy, especially over a period of time 艰苦的;艰难的
an arduous journey across the Andes 翻越安第斯山脉的艰苦之行
The work was arduous. 这项工作很艰巨。
Oversee: to watch somebody/something and make sure that a job or an activity is done correctly 监督;监视
United Nations observers oversaw the elections. 联合国观察员监督了选举。
Beforehand: earlier; before something else happens or is done 预先;事先
two weeks/three days/a few hours beforehand 提前两星期╱三天╱几小时
I wish we'd known about it beforehand. 要是我们预先知道这事就好了.
