______ acupuncture developed, the simple “bian stones” were replaced first by stone and pottery needles, and ________ by metal needles

I know nothing about American history. So when I ______ about it, I couldn’t answer it at all.

The flight attendant welcomed us ___ theplane

10. We were anxious _____ news of your safearrival.

The novel Frankenstein told the story of a scientist who _____ a monster that _____ a huge humanbeing.[ ]