Finish the second sentence in such a way that it means the same as the sentence printed before

Exercise 8. Finish the second sentence in such a way that it means the same as the
sentence printed before.
76.Jane spends 3 hours a week sorting stamps.
=>It
force.com
77.She usually writes each letter in 30 minutes.
=> It
78.It is wrong of us to throw rubbish.
=> We mustn't
79.Hoa is the best at English in her class
=>Nobody in Hoa's class
80.I am always nervous when I travel by air.
=>Travelling_
81. They are fast typists.
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