With the development of socity,fewer and fewer old man is____ in the countryside.
Without the earth’s atmosphere to protect them, astronauts can be exposed to intense radiation from the sun, ____ them at risk of cancer.
If there were no automatic washing machines, people would have to wash their clothes ______ hand or ______ hand-operated machines.
“No bread eaten by man is so sweet as______ earned by his own labour. ”
_____ the majority of people you will meet when travelling are sure to be friendly, there are dangers-theft being the most common.
Water is the most widely used resource in ______ industry, and plays ______ major role in energy production.