everyone knows that.地球人都知道
Everyone knows that a film has a script, and this script must be followed when being filmed.
大家都知道一部电影就有一个剧本，拍电影的时候就必须得照着这个剧本来拍。

sign up 跟…签订合同; 报名
Many people who sign up to facebook quickly find they have no use for it.
很多在facebook上注册的人很快就会发现，他们根本用不上它。
Attention, guests, this is your last chance to sign up for the ice-dancing contest.
注意了,大家!这是您的最后机会来登记参加冰上之舞比赛