The speech from the new government is a __________ that major changes are on the way．

After the new equipment was introduced, they produced ______machines this year as the year before.

(2013·福建毕业班质量检查)—What does PM 2.5 mean?—It's a professional ________ indicating the condition of air pollution.

We are told to read the passage and find the sentences that ________ the argument.

—Why does Thomas speak through every discussion but never listen to the others?—That's what he ________ do. We used to hate that, but are used to it now.