填空题

Dangers of Using Computer Terminals Undoubtedly, the computer has greatly increased human being’s working capacity and intellectual capacity, but it also poses dangers to its users. The problems caused by the use of computers: a. more frequent incidence of abnormity during (1)______ (1)______ b. increased stress and (2)______to vision: worsening short sight (2)______ and an itching of the face. To solve this problem, one should take a rest from time to time and place computers at a location where there is (3)______ (3)______ light and something else to look at. c. constipation resulting from long periods of sedentary (4)______ (4)______ d. (5)______due to crouching over an inconveniently positioned (5)______ keyboard. e. a sense of (6)______owing to having puzzled over a problem too (6)______ long. Precautions computer users are advised to take: Firstly, to make sure that there is an alternative source of light from that of the (7)______itself. (7)______ Secondly, to rest their eyes frequently. In addition, to make sure the screen is properly (8)______ (8)______ Finally, to make sure that you are sitting in a comfortable position, to get up (9)______and go out into the fresh air occasionally. Sitting still for (9)______ hours is likely to cause thrombosis and (10)______ (10)______