Instructions. Rewrite the sentence by omitting the subject and using the present participle. Example: You should pay attention when you are driving. You should pay attention when driving.
Explanation
In time clauses with after, before, while, and when the subject can be omitted and the present participle (verb+ing) can be used.
After I ate lunch, I went shopping. After eating lunch, I went shopping.
Carla and her sister studied English at UNAM while they were living in San Antonio.
After Henry graduated from college, he got a job with an engineering company.
Before you leave the office, please turn off all the lights.
You should have done more research on the house before you bought it.
While Nathan was walking to school, he was thinking about what happened yesterday.
Before you buy a new laptop computer in a store, it's a good idea to check prices on the Internet.