it is a complex because a complex sentence is a sentence containing an independent clause and a subordinate clause. Lisa is the subject, got sent is your verb, and your object is office. so that is your independent clause. the other part is your subordinate clause. a subordinate clause is an incomplete thought. start at the word because and try to read it. because she was late.<-it doesn't make sense because it isn't a complete thought. the word "was" is your verb and "she" is your subject. since it has "because" it automatically makes it a subordinate clause. search up subordinating words and because is one of them.
I am in AP(college class) English 3 c:
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