When is it appropriate to use e-mail rather than the postal service to send a letter of complaint?

When sending a complaint to a large company such as UPS or maybe               you have a complaint with your doctors office. You should then send a email 

This is what i found “an elliptical clause is a type of dependent, or subordinate, clause that is missing a word or words. often, the missing part is a verb or verb phrase. while elliptical clauses are acceptable to use, they can sometimes cause confusion for writers and readers, especially when the sentence ends with a pronoun.” i hope this you for what your looking for. can you plz mark me brainliest?