Companies are struggling to find the right _____between supply and demand, but it is no easy work .
It remains________ whether Jim will be fit enough to play in the finals.
Professor Williams keeps telling his students that the future________ to the well-educated.
There is no doubt _______ my friend is not satisfied with what they have done.
We should learn from those _____ are always ready to help others.
Friends should be_____ about each other’s feelings.