Hefellasleepimmediatelylastnight;hemust________(be)verytired.
Wooddoesnotconductelectricity;________.
Heaskedmewhethermybrother________(fly)toBeijing.
heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.
Herefusedtotelluswhetherhe________(undertake)thejob.
Iwonderifhecouldgetit________(do)beforetomorrow.
