heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.
Hardlyhadhefinishedhisspeech________theaudiencestartedcheering.
Herefusedtotelluswhetherhe________(undertake)thejob.
Thefloordoesnotlooksobadwhen________(sweep)clean.
________(fail)severaltimes,theyneedsomeencouragement.
