The _________ water that killed all the fish in the lake contained high levels of mercury.

A sudden _________ of hungry locusts left the region without crops as the insects attacked and devoured everything.

_________ species from other habitats can harm ecosystems by competing with native species for food and space.

Be sure to _________ to the radio show tonight at 7:00 pm to hear the latest news and music.

_________ are a type of fish that live in rivers and lakes and spread easily to other areas.

Several important American _________ , such as the Mississippi River, are filling up with invasive fish species which disrupt local aquatic ecosystems.

This endangered species of turtle is _________ of disappearing, unless it can find a way to adapt.

Lots of animals _________ every year, such as birds that fly south to find warmer weather and food in winter.

The _________ brought together leaders from several countries to discuss solutions for climate change.

The turtles _________ to disappear from that area until they learnt how to protect their eggs from predators.

Humpback whales were expected _________ and disappear forever as a species, but they are now making a comeback.

Endangered species can live and breed in _________ , where they are kept safe from hunters.

We spent three hours _________ at the clean-up event, working without a break.

The volunteers spent the day _________ rubbish out of the lake.

The children were playing and _________ at the campsite, and didn't realise how big a mess they were making!

After cleaning the beach all day, we were so hungry that we _________ our food in minutes.

Jessica wanted to volunteer for the clean-up event at the river, but she _________ out when she saw how muddy it was.

David is _________ all of the money that he's earning from his job so that he can travel next year.

Angela decided to _________ the city council about the pollution problems that they had been ignoring.

By teaching the young people of today how to better care for the environment, we _________ of a healthier planet in the future.

You can complain to the mayor _________ , but he will never agree to ban cars from the city centre.

She accused the teenagers of leaving their rubbish on the beach, but she is _________ because they didn't.

The town council needs to stop _________ and come up with a plan for dealing with litter.

Some species of birds _________ to warmer global temperatures by migrating to cooler regions.

Lots of fish in this river have died from _________ to toxic chemicals that were dumped by nearby factories.

You can often see lots of wildlife _________ the town as this is where it meets the countryside.

There is more wildlife to be found _________ than in the city centre.

The _________ that holds the hot water is located behind the house.

Engineers built a strong _________ across the river in order to stop water from flooding the area during heavy rains.

We sailed our boat on the river, out of the _________ and into the open sea.

To improve the growth of her tomatoes, Nancy uses a natural _________ that doesn't contain chemicals.

Farmers spray _________ on their crops to protect them from harmful insects.

Farmers often use herbicides to control the growth of weeds and other unwanted plants in their fields.

The gardener used an _________ to keep harmful bugs away from his vegetables.

Heavy rain caused _________ to the side of the hill, washing away much of the soil.

The metal storage tank showed damage from _________ after years of holding harmful chemicals.

The constant _________ from using cleaning products over a long period of time caused damage to the surface of the metal.

An army fights a war of attrition by repeatedly attacking until the enemy slowly loses its strength and surrenders.

Lions are _________ and can eat 43 kilos of meat a day.

Gorillas are _________ that survive mainly on a plant-based diet.

A bear is an _________ that eats plants as well as fish and other small animals.

Frogs are _________ that eat flies and other bugs.

Unfortunately, time is running out for several species of fish as high levels of water pollution are causing them to disappear.

Some species of butterflies use _________ to disguise themselves as dangerous insects in order to frighten away predators.