I have another question. Please take a look at the following sentence (error correction)
The more Robert tried to please his mother with mere flattery, the greater he succeeded in annoying her.
In the said sentence, the answer key says that the wrong part is the "the greater", which, accordingly, must be replaced with " the more greatly".
Why is " the greater" wrong here? I haven' t used " the more greatly" before, as this one.