Page 295 - Practical English Usage 3ed - Michael Swan, Oxford

infinitives (9); active and passive infinitive with similar meaning 287
287 infinitives (9): active and passive infinitive with similar meaning
1 obligation
We can use noun + infinitive to talk about obligation - things that people have to do. Active and passive infinitives are often both possible.
There's a lot of work to do I to be do1U!.
There are six letters to post I to be posted.
Give me the names o f the people to contact I to be contacted. The people to interview I to be interviewed are in the next room.
We prefer active infinitives if we are thinking more about the person who will do the action.
I've got work to do. (NOT I've gtJt ftltJrk 16 he ti6f'/;e.)
They've sent Ja1U! a form to fill in.
We use passive infinitives if we are thinking more about the action, or the person/thing that the action is done to.
The carpets to be cleaned are in the garage. (NOT The etu'1'ets t6 eietl;lt ...)
His desk is covered with forms to be filled in.
After be, we normally use passive infinitives in these cases.
These sheets are to be washed. (NOT These sheets are 16 wash.) This form is to be filled in in ink. (NOT Thi5 Iei'm i5 t6 Jill in ...) The cleaning is to be finished by midday. (NOT ••• i5 t6 jini5h ...)
2 to be seen/found/congratulated etc
Note the expressions anywhere/nowhere to be seen/found.
He wasn't anywhere to be seen. (NOT••• anywhere t6 see.) Susan was nowhere to befound. (NOT ••• n6ft/here t6 Jinti.)
We also use passive infinitives to express value judgements with verbs like
congratulate, encourage, avoid.
You are to be congratulated. (NOT ••• 16 oongmtuiate.) This behaviour is to be encouraged.
But note the common expression to blame, meaning 'responsible' (for some unfortunate event).
Nobody was to blame for the accident.
3 nothing to do and nothing to be done etc
Note the difference between nothing to do and nothing to be done. I'm bored - there's nothing to do. (= There are no entertainments.) There's nothing to be do1U! - we'll have to buy a new one.
(= There's no way of putting it right.)
For structures like Size's easy to amuse, see 284.4.
For structures with take (e.g. Tize ferry took truo hOllrs to unload), see 576. For more about be + infinitive, see 91.
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