Hello, fellas. Last week we learned how to reduce relative clauses.
(More on reduced relative clauses: https://englishtips4u.com/2018/07/26/grammartrivia-reduced-relative-clauses/)
In this session, we are still going to discuss the reduction of clauses. It is the reduction of adverb clauses of time.
(More on adverb clauses of time: https://englishtips4u.com/2011/10/13/engclass-adverbial-clause/)
In a sentence, an adverb clause functions as the dependent clause. It must be attached to the main clause or the independent clause (More on clauses: https://englishtips4u.com/2018/01/26/engclass-clause/). An adverb clause of time begins with a conjunction, such as after, before, since, when, and while.
The reduction of an adverb clause of time to an adverbial phrase is only possible when its subject is the same as the subject of the main clause. There are two ways of reducing the adverb clause of time:
1) Omit the subject and be
While I was studying, I fell asleep.
While studying, I fell asleep.
2) If there is no be, omit the subject and change the verb to its –ing form
Jane has lived abroad since she pursued her education.
Jane has lived abroad since pursuing her education.
Betty Schrampfer Azar, Understanding and Using English Grammar: Third Edition