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Detached/impersonal styles

482b

Agentless passives are conventionally used in impersonal speaking and writing

styles (e.g. academic and technical language) when processes are the focus of

attention:

Heat 

was applied until the mixture came to the boil.

The central heating system 

has to be regularly maintained.

Vitamin tablets 

should be taken daily.

Such impersonal uses often involve reporting verbs such as believe, consider, find,

say

, think:

What is poverty? Much of the debate centres on what level of income 

is

considered to be the poverty level. 

[scientific text about birds: young here means ‘young birds’]

Losses of eggs and young 

were found to be relatively constant throughout the

season, even though their numbers increased dramatically for a short time.