Sentence written w/ and w/o participles - passive vs active voice

Question

In Nicholas J. Brown's book, exercise 27/4 has a sentence, roughly expressing the same idea (with and without Past Passive Participles [short,perfective,transitive]) and the question and answer are in the pictures.

My primary question was about the last pair of PPP and past perfective verb, but an additional very related part may ask about mood - I'm not sure it is a good idea to split into two questions...

and translations;

Clearly, PPPs are passive, and I would say that past tense verbs are active. Here are some from the two situations;

1. уже проданы / уже продали : 'had already been sold' / 'had already sold' - Is this a passive construction versus an active construction?

2. В среду было объявлено / В среду объявили : 'On Wednesday it was announced' / 'On Wednesday they announced' - Also seems passive vs active

3. было написано / написал : '(it) was written' / '(the letter) wrote' - Again, passive vs active voice.

4. будут куплены / купят : 'would be bought' / '(they) would buy' - Again, passive and then active.

   4b. An aside, is this true (maybe this is starting to mix tense and mood...) 'would be bought' = 'will be bought' Actually I would have assumed this conditional English translation come from a Russian sentence with 'бы' in it?

But what happened here? Why the same?

5. Мы были очень удивлены / Мы очень удивились : 'We were very surprised' -- in both cases

   Should the first situation be translated as: 'It was surprising to us...' - too much like impersonal dative case construction?

   Maybe 'It very much surprised us'?

PS If necessary I will reword my sentence upon receiving suggestions.

Answer 1

1. уже проданы / уже продали : 'had already been sold' / 'had already sold' - Is this a passive construction versus an active construction?

Yes, but more accurately THEY had already sold, in Russian it's an impersonal construction.

2. В среду было объявлено / В среду объявили : 'On Wednesday it was announced' / 'On Wednesday they announced' - Also seems passive vs active

Yes

3. было написано / написал : '(it) was written' / '(the letter) wrote' - Again, passive vs active voice.

Yes, but in his letter the director wrote, director is the subject here.

4. будут куплены / купят : 'would be bought' / '(they) would buy' - Again, passive and then active.

Yes

4b. An aside, is this true (maybe this is starting to mix tense and mood...) 'would be bought' = 'will be bought' Actually I would have assumed this conditional English translation come from a Russian sentence with 'бы' in it?

No, the English would comes from the future within the past tense according to the English grammar, but in Russian it's simple future.

But what happened here? Why the same?

5. Мы были очень удивлены / Мы очень удивились : 'We were very surprised' -- in both cases

That's because English doesn't really have (at least to my limited knowledge) an equivalent of the Russian reflexive verb удивляться, that's why it's translated with past participle.

Should the first situation be translated as: 'It was surprising to us...' - too much like impersonal dative case construction?
Maybe 'It very much surprised us'?

No, because it doesn't convey the passive voice used in Russian example.
Your suggestion in Russian would look like

Это нас (очень) удивило

which is a legit construction only divergent from the wording of the original Russian sentence. Note that this is NOT an impersonal clause, because of the demonstrative pronoun это which is its subject.

It's the rendering of this clause in the 2nd sentence which could be considered problematic due to the absence of a proper equivalent in English.

If one gets creative this dichotomy can be rendered as It made us wonder vs We were wondering. But as result we lose the accuracy of the passive voice translation.