It reported that the police are _________the disappearance of the two children.

Sam spends two hours _______ his homework every day.

Sandy asked his brother about the news in a voice. [ ]

The boy is afraid ______ his mother because she is very strict _____ him.

e is less and less coal and oil, scientists are exploring new ways ofmaking use of ______ energy, such as sunlight, wind and water for power andfuel.