Wah How to use Before and After with Gerund.

We can use Before and After with Subject + Verb or Gerund.

With Subject + Verb
    I went to the U.S. after I left school.

With Gerund
    I went to the U.S. after leaving school.

Note: Both of them have the same meaning as long as the subject is the same.

    Before Jason gets to work, he always buys a milkshake. 
    Before getting to work, Jason always buys a milkshake.

    After I decided, I started to worry about my decision. 
    After deciding, I started to worry about my decision. 

    Before you went to Maldives, how did you prepare? 
    Before going to Maldives, how did you prepare? 

    After you watch a good movie, what would you like to do? 
    After watching a good movie, what would you like to do? 

    Before John became a millionaire, he never enjoyed his life.
    Before becoming a millionaire, John never enjoyed his life.

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