Heaskedmewhethermybrother________(fly)toBeijing.

Themorewelookedatthepicture,________.

I shall never forget ________ (meet) the late Premier Zhou during his inspection of our factory.

________(fail)severaltimes,theyneedsomeencouragement.

heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.