He is very popular among his students as he al-ways tries to make them _______in his lectures.
—Are the new machine working?—Yes. Three million tons of coal________exploited every year in the city.
Everyone here thanks the firefighters for the things they have done to prevent fires________the environment safer.
He tried to________to cook a meal on the island but he failed.
Bajin, for________experiences were dangerous and unforgettable, was an old man always telling the truth.
________bird flu outbreak has killed 545 chickens and ducks in________central China and led authorities to destroy 2,487 others.