Переделайте предложения, используя модальные глаглы «must», «should», «ought to».
1 Do not stare at the screen for long periods of time.
2 Avoid placing the monitor so that it reflects bright light, such as a Window.
3 Keep the screen clean to prevent distorting shadows.
4 If you work in an office with a large number of computers, don’t sit too close to the sides or
backs of the monitors.
5 Buy a protective filter that cuts down the Extremely Low Frequency emissions.
Объяснение:
you shouldn't stare at the screen for long periods of time.