Some teenagers _______ their health because they often expose themselves to so many electric products.
| A．have damaged | B．are damaging | C．damaged | D．will damage |
In____review of 44 studies, American researchers found that men and women____who ate six key foods daily cut the risk of ______ heart disease by 76%. 
| A．a; the | B．the; a | C．a; 不填 | D．不填； a |
Washing machines made by China have won ____worldwide attention and Haier has become _____ popular name. 
| A．a; the | B．/; a | C．/; the | D．the; a |
People think that ______ opening ceremony of the 29th Olympic Games is _____ great success. 
| A．an; a | B．the; a | C．the; the | D．the; / |
— Is Mr Smith rich? 
— Yes, very rich. When he worked in ________town, he earned a lot. Now he has a big farm in ________ country.
| A．at; the | B．/; / | C．/; the | D．the; / |
In science fiction we read of flying saucers travel through _____ space, so people want to have ______ better knowledge of the universe. 
| A．the; a | B．/; / | C．the; / | D．/; a |