Very much; to a great extent; a lot; lots. (adverb)
A large amount; a lot. (noun)
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Use "a good deal" in a sentence
"This speedy rate of adoption occurred because the drug problem was high on the public agenda in the late 1980s (Dearing and Rogers, 1996), and also because a good deal of re-invention took place (Rogers, 1993a)."
"Our core thesis, Presentation Mastery, co-written by my two partners George Lowe and Greg Kaiser, formed the basis for a good deal of what I have written here on that subject."
"Remind yourself that a good deal of research has shown that memories of past events are fragile and unreliable and can easily be distorted.8 Ashleigh Brilliant, who was skeptical of the truth in recovered memories of childhood abuse that appeared after decades, said, “Some of the things that will live longest in my memory—never really happened.”"