Cambridge Grammar of English Hardback with cd-rom a comprehensive Guide

To-infinitive 

To

-infinitives may occur as simple non-tensed phrases:

To cope with the extra traffic caused by the university, a new £7-million road

bridge will be built over the River Witham.

400 | Verb phrase 1: structure of verb phrases

Cambridge Grammar of English

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They may also be used with be and the -ed participle as passive voice phrases:

To be deprived of even one hour of sleep was another step towards total

exhaustion and collapse. 

They also occur with have and the -ed participle to indicate perfect aspect:

To have got the 8 o’clock flight would have meant getting up at 4.30.

They also occur with the -ing participle to indicate progressive aspect:

How cruel 

to be having it now, when it was too late.

Combinations of these structures may also be found:

Well I’ve heard they’re supposed 

to be being pulled down. 

(progressive and passive)

And you felt that she ought 

to have been informed about that? 

(perfect and passive)

Whales and other marine animals are thought 

to have been being killed as a

result of the military tests.

(perfect, progressive and passive)