He keeps working late in the night _____ catch up with others. A. in order toB. forC. so as toD. both A and C
He keeps working late in the night _____ catch up with others.
A. in order to
B. for
C. so as to
D. both A and C
相关考题：
After several failures, Tom still () in doing the experiments. A.carries onB.insistsC.persistsD.keeps
共用题干第二篇Late-night DrinkingCoffee lovers,be careful.Having a quick "pick-me-up" cup of coffee late in the day will interrupt your sleep. As well as being a stimulant（兴奋剂）,caffeine interrupts the flow of melatonin（褪黑激素）,thebrain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime.Levels then peak between 2 am and 4 am , before falling again. " It 's the neurohormone（神经激素）that controls our sleep and tells our body when to sleep and when to wake,"says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California. But researchers in Israel have found that caffeinated coffee halvesthe body'S levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical center in Tel Aviv University found that six volunteers sleptless well after a cup of caffeinated coffee than after drinking the same amount of decaf（脱咖啡因咖啡）.On average,subjects slept 336 minutes per night after drinking caffeinated coffee,compared with 415 minutes after decaf. They also took half an hour to drop off,twice as long as usual.In the second phase of the experiment,the researchers woke the volunteers every three hours and asked them to give a urine（尿）sample.Shilo measured concentrations of a breakdown product of melatonin.The results suggest that melatonin concentrations in caffeine drinkers were half those in decaf drinkers.In a paper accepted for publication in Sleep Medicine,the researchers suggest that caffeine blocks production of the enzyme（酶）that drives melatonin production.Because it can take many hours to eliminate caffeine from the body.Ohayon recommends that coffee lovers switch to decaf after lunch. The author mentions "pick-me-up" to indicate that_______.A:melatonin levels need to be raisedB:coffee is a stimulanC:neurohormone can wake us upD:caffeine can balance our brain hormone
共用题干Late-night DrinkingCoffee lovers,be careful. Having a quick “pick-me-up” cup of coffee late in the day will interrupt your sleep. As well as being a stimulant（兴奋剂）,caffeine interrupts the flow of melatonin（褪黑激素）,the brain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am, before falling again.“It's the neurohormone（神经激素）that con-trols our sleep and tells our body when to sleep and when to wake,”says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California. But researchers in Israel have found that caffeinated coffee halves the body's levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six volunteers slept less well after a cup of caffeinated coffee than after drinking the same amount of decaf（脱咖啡因咖啡）.On average, subjects slept 336 minutes per night after drinking caffeinated coffee,compared with 415 minutes after decaf. They also took half an hour to drop off,twice as long as usual.In the second phase of the experiment,the researchers woke the volunteers every three hours and asked them to give a urine（尿）sample. Shilo measured concentrations of a break-down product of melatonin. The results suggest that melatonin concentrations in caffeine drinkers were half those in decaf drinkers. In a paper accepted for publication in Sleep Medi-cine,the researchers suggest that caffeine blocks production of the enzyme（酶）that drives melatonin production.Because it can take many hours to eliminate caffeine from the body. Ohayon recommends that coffee lovers switch to decaf after lunch.The author mentions“pick-me-up” to indicate that______.A: melatonin levels need to be raisedB: coffee is a stimulantC: neurohormone can wake us upD: caffeine can balance our brain hormone
共用题干Late-Night DrinkingCoffee lovers beware .Having a quick"pick-me-up"cup of coffee late in the day will play havoc with your sleep.As well as being a stimulant,caffeine interrupts the flow of melatonin,the brain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime.Levels then peak be-tween 2 a.m.and 4 a. m.,before falling again."It's the neurohormone that controls our sleep and tells our body when to sleep and when to wake,"says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California. But researchers in Israel have found that caffeinated coffee halves the body's levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six vol- unteers slept less well after a cup of caffeinated coffee than after drinking the same amount of de-caf（脱因咖啡）.On average , subjects slept 336 minutes per night after drinking caffeinated cof-fee,compared with 415 minutes after decaf. They also took half an hour to drop off-twice as long as usual-and jigged around in bed twice as much.In the second phase of the experiment,the researchers woke the volunteers every three hours and asked them to give a urine sample,Shilo measured concentrations of a breakdown product of melatonin .The results suggest that melatonin concentrations in caffeine drinkers were half those in decaf drinkers.In a paper accepted for publication in Sleep Medicine,the researchers suggest that caffeine blocks production of the enzyme that drives melatonin production.Because it can take many hours to eliminate caffeine from the body,Ohayon recommends that coffee lovers switch to decaf after lunch. The author mentions" pick-me-up" to indicate that______.A: decaf is a caffeinated coffeeB: coffee is a stimulantC: neurohormone can wake us upD:melatonin levels need to be raised
共用题干Late-Night DrinkingCoffee lovers beware.Having a quick"pick-me-up"cup of coffee late in the day will play havoc with your sleep .As well as being a stimulant,caffeine interrupts the flow of melatonin,the brain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime. Levels then peak be-tween 2 am and 4 am,before falling again."It's the neurohormone that controls our sleep tells our body when to sleep and when to wake,"says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California.But researchers in Israel have found that caf feinated coffee halves the body's levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six vol-unteers slept less well after a cup of caffeinated coffee than after drinking the same amount of de-caf. On average,subjects slept 336 minutes per night after drinking caffeinated coffee,compared with 415 minutes after decaf. They also took half an hour to drop offtwice as long as usual-and jigged around in bed twice as much.In the second phase of the experiment,the researchers woke the volunteers every three hours and asked them to give a urine sample.Shilo measured concentrations of a breakdown product of melatonin .The results suggest that melatonin concentrations in caffeine drinkers were half those in decaf drinkers .In a paper accepted for publication in Sleep Medicine,the researchers suggest that caffeine blocks production of the enzyme that drives melatonin production.Because it can take many hours to eliminate caffeine from the body,Ohayon recommends that coffee lovers switch to decaf after lunch. The author of this passage probably agrees that______.A: coffee lovers sleep less than those who do not drink coffeeB: we should not drink coffee after supperC: people sleep more soundly at midnight than at 3 a.m.D: if we feel sleepy at night,we should go to bed immediately
共用题干Late-Night DrinkingCoffee lovers beware.Having a quick"pick-me-up"cup of coffee late in the day will play havoc with your sleep .As well as being a stimulant,caffeine interrupts the flow of melatonin,the brain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime. Levels then peak be-tween 2 am and 4 am,before falling again."It's the neurohormone that controls our sleep tells our body when to sleep and when to wake,"says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California.But researchers in Israel have found that caf feinated coffee halves the body's levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six vol-unteers slept less well after a cup of caffeinated coffee than after drinking the same amount of de-caf. On average,subjects slept 336 minutes per night after drinking caffeinated coffee,compared with 415 minutes after decaf. They also took half an hour to drop offtwice as long as usual-and jigged around in bed twice as much.In the second phase of the experiment,the researchers woke the volunteers every three hours and asked them to give a urine sample.Shilo measured concentrations of a breakdown product of melatonin .The results suggest that melatonin concentrations in caffeine drinkers were half those in decaf drinkers .In a paper accepted for publication in Sleep Medicine,the researchers suggest that caffeine blocks production of the enzyme that drives melatonin production.Because it can take many hours to eliminate caffeine from the body,Ohayon recommends that coffee lovers switch to decaf after lunch. The author mentions"pick-me-up" to indicate that______.A: melatonin levels need to be raisedB: neurohormone can wake us upC: coffee is a stimulantD: decaf is a caffeinated coffee
下面语句执行后，变量w中的值是____。 w=Choose（2 , "Morning", "Afternoon", "Day", "Night",)A．MorningB．AfternoonC．DayD．Night