The passive compared with adjectival past participles

Many words such as broken, interested, shut, worried [> 6.14-15, 7.51]
can be used either as adjectives or as past participles in passive
constructions. A difference can be noted between:
/was worriedabout you all night (adjective: a state)

/ was worried bymosquitoes all night (passive: dynamic verb) If the word is an adjective, it cannot be used with by + agent and cannot be transposed into a sentence in the active.

12.8 The passive with verbs of 'saying' and 'believing'

We need to be sure of our facts in a statement like Muriel pays less income tax than she should. It is often 'safer' to say e.g. Muriel is said to pay less income tax than she should. If it seems necessary to be cautious, we can use passive constructions like the following:

1 l t ( + passive + that-clause) with verbs like agree, allege, arrange, assume, believe, consider, decide, declare, discover, expect, fear, feel, find, hope, imagine, know, observe, presume, prove, report, say, show, suggest, suppose, think, understand It is said thatthere is plenty of oil off our coast It is feared thatmany lives have been lost in the train crash

2 There (+ passive + to be + complement) with a limited selection of verbs: e.g. acknowledge, allege, believe consider, fear, feel, know, presume, report, say, suppose, think, understand:

There is said to be plenty of oil off our coast

There are known to be thousands of different species of beetles

12 The passive and the causative

3 Subject other than it (+ passive + to-infinitive) with a few verbs: e.g. acknowledge, allege believe, consider declare, know, recognize, report, say, suppose, think, understand Mandy is saidto be some kind of secret agent Turner was consideredto be a genius even in his lifetime Homeopathic remedies are believedto be very effective Other verbs beside be are possible in the infinitive: Jane is said to know all there is to know about chimpanzees Note how suppose has two different meanings in: He is supposed to be at work at the moment This can mean 'People think he is at work' or 'It is his duty to be at work'. There + be also combines with suppose There is supposedto be a train at 12 37

Some typical contexts for the passive

Formal notices and announcements

Candidates are requiredto present themselves fifteen minutes before the examination begins They are askedto be punctual Passengers are requestedto remain seated until the aircraft comes to a complete stop [compare > 11.23].