更多"Drugs can be divided into three mai"的相关试题:
[填空题]Drugs can be divided into three main groups: those that a person can buy without a prescription. those that a person needs a doctor’s prescription for, and those that are illegal.
Two popular nonprescription drugs are caffeine (咖啡因) and alcohol. Caffeine is found in coffee, tea, chocolate, and cola drinks. It is a mental stimulant; it stimulates the central nervous system and makes people feel alert. Students, for example, often find they can study better if they have a cup of coffee. On the other hand, caffeine can also make people nervous and irritable. If people drink too much caffeine, they may have trouble sleeping.
Alcohol is a depressant; it depresses the central nervous system. When people drink, they have less control over their actions. They cannot walk in a straight line and they cannot drive as well as when they are alcohol-free in their blood. People who drink a great deal sometimes fall into a deep sleep. Later, they may wake up with a strong headache.
[单项选择]Novel drugs developed through biotechnologies can be expected to deliver a better effect.( )
A. distribute
B. produce
C. liberate
D. express
[填空题]How many groups can people be divided into
They can be dividen into ______ groups.
[填空题]
How many groups can music be divided into
Music().
[单项选择]
Animals are divided into many groups. Some groups of animals include the, insects, fish, amphibians, reptiles, birds and mammals.
Insects are small animals that have six (21) legs and three body parts (the (22) , the thorax, and the abdomen). Many insects can fly; flying insects have one or two (23) of wings. Some flying insects include butterflies, moths, dragonflies, flies, and mosquitoes. Some (24) insects include springtails, fleas, and lice.
Fish are swimming animals that have scales and fins. Fish (25) oxygen that is dissolved in the water using gills. Most fish have bony skeletons, but some, (26) sharks and rays, have only cartilage.
Amphibians are animals that (27) their life in the water, breathing with gills. As they grow, they breathe air using lungs, and many (28) the land. Some amphibians include frogs, toads, salamanders, and newts.
Reptiles are cold-blooded animals (29)
A. non-flying
B. running
C. jumping
D. racing