(2012浙江卷) The development of industry has been_______ gradual process throughout _______ human existence, from stone tools to modern technology.
When ___for his views about his teaching job, Philip said he found it very interesting and rewarding.
The professor spoke very clearly to make his speech ___.
Her ___ look suggested that she was completely ___.
“Bill, keep the things ___ here secret,”said the manager after meeting.
It is one of the funniest things ___ on the Internet so far this year.