What is needed in the case of noise is a study of large numbers of people living under noisy conditions, to discover whether they are mentally ill more often than other people are. 

in the case of ^{with reference to, or in the situation of 对于，关于；在……情况下}

• The law will apply equally to men and women except in the case of maternity leave.
• The amount of fruit in fruit juices must be 6% in the case of berries and 10% in the case of other fruits.

study of ^{对于…的研究}

• a study of Australian wild birds
• a center for the study of Asian languages
• We conducted a study of consumer behavior in rural areas.

conditions ^{n. [pl.] circumstances 环境，情况(under ... conditions 在…环境中)}

• Under existing conditions, the plan cannot succeed.
• Firemen have to operate under very difficult conditions. ^{在非常艰苦的环境中}
• The soldiers survived under harsh conditions. ^{在恶劣的环境中}

Some time ago the United States Navy, for instance, examined a very large number of men working on aircraft carriers: the study was known as Project Anehin.

Some time ago ^前不久

• Some time ago, an interesting discovery was made by archaeologists on the Aegean island of Kea. ^前不久
• Some time ago, I received a letter from an old friend. ^前不久
• We had a similar conversation some time ago. ^前不久
• When a light passenger plane flew off course some time ago, it crashed in the mountains and its pilot was killed.

aircraft carrier ^{n. a type of ship that planes can fly from and land on 航空母舰}

• He served on an aircraft carrier during the war.
• The aircraft carrier launched several jets during the exercise.
• An aircraft carrier can carry dozens of planes.

It can be unpleasant to live even several miles from an aerodrome; if you think what it must be like to share the deck of a ship with several squadrons of jet aircraft, you will realize that a modern navy is a good place to study noise.

aerodrome ^{n.a place that small planes fly from 小飞机场}

• The small plane landed safely at the aerodrome. ^小飞机场
• There is an aerodrome just outside the town.
• The pilot trained at a local aerodrome. ^小型机场

squadron ^{n.a unit of one of the armed forces, especially the air force or the navy 空军或海军中队}

• A squadron of jets flew overhead.
• The navy deployed a squadron for the mission.
• He commands a squadron in the air force.

jet aircraft / jet ^{n.aircraft powered by a jet engine 喷气式飞机}

• Jet aircraft are faster than propeller planes.
• They heard the roar of a jet aircraft overhead.
• The military uses many jet aircraft.

But neither psychiatric interviews nor objective tests were able to show any effects upon these American sailors.

neither ... nor ^{既不…也不…}

• Neither the manager nor the workers knew what to do.
• Neither John nor Mary was present at the meeting. 
• She could neither read nor write at that time. 

This result merely confirms earlier American and British studies: if there is any effect of noise upon mental health, it must be so small that present methods of psychiatric diagnosis cannot find it.

if ^{if + 从句不一定是条件，也有可能是让步（if = even if  即使），要根据上下文判断。}

• But the first people who were like ourselves lived so long ago that even their sagas, if they had any, are forgotten.
• God’s reasons, if He has any, are opaque to us.
• If he has any reasons, they are unknown to us.
• His descendants, if any, never left the island.

If there is any effect of GM foods upon human health, it must be so small that present methods of medical diagnosis cannot find it. ^{即使转基因食品对于人体健康有影响，也一定是微乎其微，以至于目前的医学诊断方法无法发现。}

• His descendants, if any, never left the island.
• He is seldom, if ever, absent from work.

There is every likelihood that the costs of the monitoring system, such as the purchase, maintenance and updates of software, employment of extra personnel in charge of it, will offset or even outweigh additional revenue, if there is any. ^{Gre写作范文}

if = although perhaps ^{尽管可能…}

• Donald's essays are always interesting, if sometimes poorly written. 
• She understood his meaning, if not his words, and took his advice.

That does not prove that it does not exist; but it does mean that noise is less dangerous than, say, being brought up in an orphanage -- which really is a mental health hazard.

say ^{比方说（插入语）}

• No matter where you live, you would find it difficult not to laugh at, say, Charlie Chaplin's early films. ^比方说
• The Americans would hammer out different pacts covering, say, electronic goods and drug manufacturing. ^比方说
• You could invest in, say, a small restaurant or shop. ^比方说

bring up sb. ^{抚养长大;把某人抚养成人}

• Whether we find a joke funny or not largely depends on where we have been brought up.
• He did not marry again and I was brought up without a woman's care; but I lacked for nothing, for he was both father and mother to me.
• He was brought up without a mother.
• We were brought up to be respectful to others.
• She was brought up in a small village.

hazard ^{隐患，危险}

• The busy traffic entrance is / presents / poses / constitutes a hazard to pedestrians.
• Our knowledge of the oceans a hundred years ago was confined to the two-dimensional shape of the sea surface and the hazards of navigation presented by the irregularities in depth of the shallow water close to the land.
• Smoking is a major health hazard. ^健康隐患
• Polluted water poses a hazard to marine life.
• That abandoned building is a safety hazard. ^安全隐患