We should try to substitute other verbs. Sometimes, however, attempts to substitute a livelier verb changes our meaning. The progressive form brings a particularly interesting bit of subtlety to English. In all its manifestations, present, past, and future, it has similar meanings, but it has the most meanings in the present. Imagine the difficulty that ESL speakers and writers have, learning the rules for these subtle uses of the progressive rules that native speakers have mastered intuitively.
Passives are among the most misunderstood verb forms in the language.
First, a lot of people confuse them with linking verbs and progressives, simply because of the presence of be . The other misunderstanding, much more widespread, concerns whether one should use the passive or not. Many people preach that we should never use the passive. Computer grammar checkers typically flag passives and advise writers to change them. This negative attitude ignores the fact that the passive has a perfectly respectable pedigree in English.