It is necessary for children to exchange ideas with parents from time to time so that the generation gap between parents and children can be _____.
It is essential that every child _______ the same educational opportunities.
The scientists are beating their brains trying to _______ a solution to the problem.
It was _______ back home after the experiment.
With the price of pork and eggs _______ quickly, CPI has become a hot phrase among Chinese.
To improve the quality of our products, we asked for suggestions _______ had used the product.