A beam of light will not bend round corners unless ________ (make) to do so with the help of a reflecting device
made
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Thistest________anumberofmultiplechoicequestions.
Onlywhenyouhaveobtainedsufficientdata________cometoasoundconclusion.
heteachertoldthemsincelight________(travel)fasterthansound,lightning________(appear)togobeforethunder.