I am doing some researches to understand clearly the usage of rather than. However I found myself even more confused by some peripheral stuff.
In this post (Past tense and "rather than"), the American Heritage dictionary was being quoted to illustrate the proper usage of rather than. It is stated that, in some cases, rather than can only be followed by a gerund. It gave as an example this sentence:
"The result of the study, rather than ending the controversy, only added to it".
It states that if end or ended had been used, the sentence would be wrong because "...the main verb has a form which would not allow parallel treatment of the verb following rather than."
I am confused by this statement. Could someone explain to me, what does "the main verb has a form which would not allow parallel treatment" in this context mean?
By the way, I am still very confused about the usage of rather than, can anyone point me to a comprehensive source so that I could really grasp the idea?