One of the most important questions they had to consider was _________ of public health.
The comments on the film, ______ this is one example, are very sharp.
He _________ English for eight years by the time he graduates from the university next year.
Try to be more careful next time. Carelessness only ______ mistakes.
The great chance he has been looking forward to _______ at last.
When ______ with any difficulty, you should not give up easily.