Herefusedtotelluswhetherhe________(undertake)thejob.
Ifound________toanswerallthequestionswithinthetimegiven.
Iknowitisn’timportantbutIcan’thelp________aboutit.
Heaskedmewhethermybrother________(fly)toBeijing.
The floor does not look so bad when ________ (sweep) clean.
Tosucceedinascientificresearchproject________.