Wemust______thattheexperimentiscontrolledasrigidlyaspossible.
A、assureIf you want to find a decent location for your own home, ________ Mr. Smith for advice.
It________asashocktorealizethatIwasnotaloneintheroom.
I bought this eighteenth century writing desk at a quite ________ price.
ShegotajobasanassistantstagemanagerattheCambridgeArtsFestivalTheatre,thinkingthatitmight________toacareerasaplaywright(剧作家).
It is useful to science _______ the earth as an object in space.
