—Are you _____ with the achievements you have made recently?      —Of course， they show my efforts at least.

The study was carried out in one small town so we can’t be sure that the results are truly ________.

Mr Brown is a(n) _____ secretary in our office, for he is able to do tasks successfully, without wasting time and energy.

Many rules in English are ______, and large numbers of students feel ______ them.

Do remember to be________. We must avoid any possible risks when doing this dangerous chemical experiment—burns, poisonous gases or cuts from broken tubes.