The development of science and __________ (technique) has made learning knowledge very easy for people.
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The factory tried to _________ (promotion) sales of its products by cutting down their prices.
Renewable energy resources can be helpful in ______ (conserve) fossil fuels and reducing carbon emissions.
The package of the new drink is ______ (environment).
The lack of electricity is still ______ (cause) the country a lotof problems.