Б) придаточными предложениями времени: I. What will you do when…
2. What did you do before…
3. What will you do after…
4. Will you stay here while…
5. Shall we go for a walk as soon as…
6. Please stay here till…

Many species of plants and animals on our planet are at risk, and in most cases they are threatened by human beings. the most common cause of extinction is loss of habitat — the places where wild animals and plants live are taken over or altered by people. the most famous example of this is the amazon rainforest in brazil. every day vast areas of rainforest are cleared to make room for farms, roads and towns. many thousands of species could be wiped out and lost forever unless the destruction of the forest is halted. there are many other examples: the giant panda has been pushed out of large areas of its natural habitat in northern; the ploughing of the north american prairies has deprived the black-footed ferret of its home; and the californian condor is being hunted to extinction by farmers