22. --- No, I’m afraid he isn’t in. This is his secretary speaking. Can I help you? --- _______.
It has always been the _____ of our firm to encourage workers to take part in social activities.
The most important _____ of his speech was that we should all work whole-heartedly for the people.
When I worked as the general manager of the firm, I sometimes had _____ to visit London on business.
As civilization______, more and more people have realized the importance of preserving rare animals from extinction.
Although I had read the book assigned by the professor several times, it didn’t make any______ to me.