[填空题]It is essential that electricity be produced at just the right______to be compatible with a utility grid.

[填空题]It is essential that electricity be produced at just the right______to be compatible with a utility grid.

[单项选择]Electricity plays an essential part in our life. No one can deny that electric light is necessary for people’s life. However, can you imagine such a world where there is no (21) of electric light As darkness falls over, children read in the light given by oil lamps and candles. Youths (22) time only by talking instead of watching TV. Everything is surrounded by (23) shadows. (24) , we have a man named Edison. He created bulb that (25) for two days before burning out. He also developed successfully a system for (26) electricity from a central powerhouse. It is he that gives us electric light, gramophone, moving pictures--all those we take (27) granted.
After the invention of electricity, manufacturers increasingly applied the findings of invention to their businesses, (28) generating new industrial growth. Development of electricity leads to the (29) creations of new products and ma
A. fired
B. glowed
C. manipulated
D. bestowed