Đồng nghĩa

Overpopulation in big cities has severely affected the air and water quality.

• seriously

• insignificantly

• largely

• commonly

I prefer to study at home because I don't want to commute between home and the library.

• carry

• follow

• direct

• travel

Although tourism is often called 'the smokeless industry', or an environmentally-friendly industry, it can actually damage nature.

• eco-friendly

• harmful

• beneficial

• disadvantageous

It is found that endangered species are often concentrated in areas that are poor and densely populated, such as much of Asia and Africa

• disappeared

• increased

• threatened

• reduced

Cuting down trees or hunting wild animals may upset the ecological balance of an area.

• strengthen

• motivate

• comfort

• disturb

The emergence of the Internet has completely changed the way people exchange information.

• appearance

• advertisement

• fascination

• deletion

Many species have become extinct each year before biologists can identify them.

• destroy

• drain

• endanger

• discover

Ecotourism needs to recruit better educated people, so it won't provide more jobs for the local people.

• reduce

• offer

• wipe out

• add

Mass tourism may cause numerous problems.

• bring in

• bring up

• bring about

• bring away

One of the approaches to reduce the impact of noise pollution on schools is to plant more trees.

• solutions

• reviews

• debates

• conclusions