She can’t help ______ the house because she’s busy making a cake.
The boy disappeared in the village five years ago and he ever since.
We've had a good start, but next, more work needs ________ to achieve the final success.
——Have you heard about that fire in the market?——Yes, fortunately no one .
They look forward a chance to receive further education.
The discovery of these tombs is ______ for scholars' studying Chinese history.