--- There is ________dark stain(污渍) on my coat. Who left it?---- It’s me, Dad. I did it just for ______ fun.
—Who is the man ________here? —Captain Cook.
—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.