We can also     1     animals in danger without ever entering their habitats.Air ,water,noise and light pollution can all have a deep and damaging     2    .Partly due to pollution     3     by ship traffic and other human activities,the dolphin population has     4     greatly .As the human population continues to grow,     5     does the effect we have on animals

Neither its cause nor its     1     was understood. So many thousands of     2    people died every time there was an outbreak. John Snow wanted to face the     3     and solve this problem. He knew that cholera would never be controlled     4     its cause was found.

England is the largest of the four countries, and for     5       it is divided     6     into three zones. ... .Although,     7    , these cities are not as large as     8    in China, they have world-famous football teams and some of them even two!

Having said this he spread some food on the table, and produced a bed from the floor. After he left, I had a     9     meal and a hot bath. Exhausted, I slid into bed and fell fast     10    .