单选题_____AlengthsBspeedsCcolorsDbrightness
单选题
_____
A
lengths
B
speeds
C
colors
D
brightness
参考解析
解析：
语篇题。承接上句，光是由不同颜色的波组成的，而我们也知道诸如红外线、紫外线这种不同颜色的光线，波长是不一样的，因此这里应选length，表示光的波长。
语篇题。承接上句，光是由不同颜色的波组成的，而我们也知道诸如红外线、紫外线这种不同颜色的光线，波长是不一样的，因此这里应选length，表示光的波长。
相关考题：
单选题When she saw the clouds, she went back to the house to _____ her umbrella.AbringBfetchCtakeDcarry
单选题Why did the country mentioned in the passage suffer from floods and starvation?ABecause an empire was set up.BBecause the empire fell to pieces.CBecause it lost all its trees.DBecause too much had been spent on wars.
单选题Why the explosion occurred was _____ the laboratory attendant had been careless.AforBbecauseCsinceDthat
单选题—We have to stop talking here. Listen, _____!—Hurry up, or we’ll be late.AThere goes the bellBThere does the bell goCThere the bell goesDGoes the bell there
单选题When she saw the clouds, she went back to the house to _____ her umbrella.AbringBfetchCtakeDcarry
单选题You’re better _____ from work tomorrow.Anot be absentBnot to absentCnot to be absentDnot absenting
单选题Why do forests in many parts of the world slowly disappear?ANew trees are not looked after properly.BMany trees have been cut down by man.CMan has not paid enough attention to planting trees.DAll of the above.
单选题It was not _____ midnight that they discovered the children were not in their beds.AbeforeBatCafterDuntil
单选题Advertisement can increase demand _____.Aall the timeBin any circumstancesCin a growing marketDin a shrinking market
单选题—I heard they went skiing in the mountains last winter.—It _____ true because there was little snow there.Amay not beBwon’t beCcouldn’t beDmustn’t be
单选题It was in that small room _____ they worked hard and dreamed of better days to come.AwhereBin whichCwhichDthat
单选题You can fly to London this afternoon _____ you don’t mind changing the plane for Paris.AprovidedBunlessCexceptDso far as
单选题The section on jokes and cartoons is _____.Aread only by childrenBof no valueCnot helpfulDread by many
单选题She found herself _____ forward more eagerly to the holiday at home.AlookingBbringingCdesiringDexpecting
单选题Breaking Mary’s doll was purely _____. John didn’t mean to do it.AincidentalBaccidentalCoccasionDopportunity
单选题A person _____ is more likely to become a genius.Awhose parents are cleverBoften thinking about difficult problemsCoften helped by his parents and teachersDborn with a good brain and putting it to active use
单选题He is unfair, _____ he?AisBisn’tCdoesDdoesn’t