"Was to " vs "was to have "

Question

What is the difference in the meaning between following sentences:

1. John was to have picked strawberries yesterday but the downpour made the field too muddy.
2. John was to pick strawberries yesterday but the downpour made the field too muddy.
   (Source: modified example from BBC http://www.bbc.co.uk/worldservice/learningenglish/grammar/learnit/learnitv103.shtml)

I've read in Learn English BBC that the form "was to" and "was to have" is used for past plan which wasn't fulfilled. But what I haven't understood is that these forms look similar to me. I'm in a dilemma which one (was to, or was to have) is used for past and which one is for unfullfilled past.

So, what are the differences between the constructions

• was/were to + infinitive
  and
• was/were to have + past participle?

Does it mean 'was to+infinitive' is used for fixed plan in the past which either did happen or didn't happen, so, the further justification is needed to know this.

On the other hand, 'was to have+p.p is a construction which itself implies that the fixed plan(sheduled in the pas) in the past didn't happen? Please make it clear with examples ? I would appreciate your helpfull answer.

Answer 1

You're parsing the construction wrong. Was to (have) is not a constituent.

Instead, they should be parsed:  

1. John [was to [have [picked strawberries]]]
2. John [was to [pick strawberries]]

Have picked strawberries is the infinitive verb phrase following to in (1),
just as pick strawberries is the infinitive verb phrase following to in (2).

Essentially, perfect infinitives like to have picked are a way to add a past tense marker to an infinitive, which is officially not allowed to mark any tense at all (that's what non-finite means).

Why would you do that? Because you might be telling a story and referring to a flashback. That allows you to call your addressee's attention to both times (the narrative time and the flashback time, one before the other) in one construction.

The be to VP idiom means 'be scheduled/expected to VP', and requires an infinitive VP.

The difference between these two sentences (not guaranteed analogous to any other sentences) is that

• John was to pick strawberries yesterday

means that he was scheduled to be starting or picking at the flashback time yesterday. If he didn't at least start, then he did no picking at all.

Whereas

• John was to have picked strawberries yesterday
  should mean that he was scheduled to be done picking at the flashback time. But it doesn't.

However, phrasing it that way is a mark of a counterfactual conditional -- i.e, starting the sentence that way alerts the addressee to be alert for a contradiction coming up soon.

Either way, with the be to VP, the focus is on a schedule, and deviations from that schedule.

Answer 2

"Was to..." construction means that something that was supposed to be done/happened in the past, is indeed done/happened.

"Was have to..." construction means that something that was supposed to be done/happened in the past wasn't actually done or didn't happen at all.

Answer 3

The difference in meaning is whether (un)successful completion of the strawberry picking task is the focal point of the reported event. The first sentence should be used if you are John's housekeeper (or John is your fieldhand), and you are explaining to your guests why no strawberries are being served. The second should be used if you are explaining to someone how John spent his day yesterday (and why he didn't spend it picking strawberries).