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Drones are a kind of machine that can fly. People use a computer to control this flying machine. Drones can do many things even without people touching them. They can carry things, go somewhere on their own and take pictures. Experts say that drones will change human life in amazing ways. Some people say this special machine will change human life as much as the car or even the computer does.
Many people around the world are using drones today. These drones can help humans solve some difficult problems. For example, filmmakers use drones to make difficult parts of films. Drones can also help to find people. If people are lost, far from home, police can use drones to find them.
In Brazil, farmers also use drones to watch their crops. Brazil has many large farms. On these farms, people find it difficult to look after all the crops. Drones can help farmers to look for crop diseases. They also help farmers use fewer farm chemicals. This can help the environment and save much money. People think that drones will be very useful in farming in thе future.
1．What’s the meaning of the underlined word “drones”?| A．电脑 | B．摄影机 | C．特斯拉 | D．无人机 |
| A．Carry things. | B．Fly. |
| C．Control computers. | D．Take pictures. |
| A．can fly high in the sky | B．can do many things without people |
| C．help filmmakers save money | D．help farmers use fewer farm chemicals |
| A．don’t need anyone to control them |
| B．are more useful than computers |
| C．can help people fight dangerous diseases |
| D．will play an important part in farming |
同类型试题
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
