he teacher told them since light ________ (travel) faster than sound,lightning ________ (appear) to go before thunder.
travels, appears
暂无解析
Heaskedmewhethermybrother________(fly)toBeijing.
Agreatnumberofsmallpowerstations________(setup)intheircounty sinceliberation.
Abeamoflightwillnotbendroundcornersunless________(make)todosowiththehelpofareflectingdevice
Iwonderifhecouldgetit________(do)beforetomorrow.
________(fail)severaltimes,theyneedsomeencouragement.