例句：Before I went to work I fed the cat.
Before going to work I wrote some letters.
Prior to doing
I had written to her prior to meeting the committee.
It was nice to be in Venice. Previously I’d only been to Rome.
It was nice to be in Venice. Before that I’d only been to Rome.
Earlier on= before then
I was in the office from 2.30. I was out earlier on.
After I’d lock up, I went to bed.
After locking up, I went to bed.
After having locked up, I went to bed.
First we went to the theatre. Then/after that, we had a meal.
He fell ill and was admitted to hospital. He died soon afterwards/after that.
Following my visit to Beijing, I bought several books about China.