He found the manager _____ by letters and papers and _____ very worried.
It has been widely accepted that only when the students take an active part in the class activities _______ the most effective.
. With the whole village _______, the villagers had to move to higher land, waiting for help.
The UN does not have its own army. _______, it borrows soldiers from different countries.
. A nature reserve for white-flag dolphins was set up in 1992, _______ boats have been prohibited from sailing around since then.
It is surprising that Jack, who is only 39 years old, _______ in the field of engineering for 20 years when he entered the company last month.