【C10】A．by contrastB．for instanceC．in additionD．however

The author explains the difference between popular and learned words ______.A．by contrastB

【C18】A．By contrastB．In a wordC．In generalD．By the way

In the opening paragraph, the author introduces his topic by______.A．posing a contrastB．ju

A．by contrastB．in practiceC．in particularD．on average

"For instance" means（).A、for exampleB、for sake ofC、at instanceD、instantly

_________[A] by chance [B] in contrast [C] as usual [D] for instance