The stroke of a pen 是什么意思呀？

with/at the stroke of a pen

大笔一挥、轻而易举地

He had the power to order troops home at the stroke of a pen.

他大笔一挥就可以下令撤回军队。

Politicians know they cannot create a lawful society simply at the stroke of a pen.

政治家知道，他们无法轻而易举地创建一个法制社会。

The intro 

(Listening Comprehension)

Hello, ladies and gentlemen. Today we're gonna start off with a joke, here we go: 

A boy comes up to his father one day and asks him, "What's the difference between POTENTIALLY and REALISTICALLY ?" His father replied, "Go ask everyone if they would sleep with Brad Pitt for a million dollars. Come back tomorrow and tell me your answer." So the boy went to his sister first and asked her, "Would you sleep with Brad Pitt for a million dollars ?" His sister replied, "A million dollars ? Heck, I'd sleep with him for free !" Then the boy went to his mother and asked her, "Would you sleep with Brad Pitt for a million dollars ?" His mother replied, "A million dollars is a lot of money ! Of course I would. It would pay for your college tuition fees and everything !" Afterwards, the boy went to his older brother's room and asked him, "Would you sleep with Brad Pitt for a million dollars ?" His brother replied, "Duh, do you know how much money a million dollars is ? I could buy a whole lot with that much money !"

The next day, the boy's father asked him if he had found out the difference between POTENTIALLY and REALISTICALLY. The boy answered, "Potentially, we could be sitting on three million dollars. Realistically, we're living with two sluts and a queer." 

Haha, alright let's talk about the phrase of the day which is "at the stroke of a pen". Check it out !

没看懂？请自己查字典！

(这才是真正的学习过程)

Brad Pitt（好莱坞电影明星）