单项选择题A.portionB.percentageC.proportionD.fraction
单项选择题A.BecauseB.WhileC.SinceD.When
单项选择题A.live up toB.catch up onC.put up withD.keep up with
单项选择题A.chanceB.timeC.momentD.occasion
单项选择题A.as usualB.as wellC.as beforeD.as such