49.You should have told me there was no class today.I —all the way
here through the heavy rain.A.must not have run B.need not have run C.should not have run D.can not have run 为么选B不选C.50.___ your timely warning ,we would have been unaware of the danger.A.in spite of B.but for C.instead of D.As for为么选B而不选 D.