all tenses in one exercise - from Bywater's A Proficiency Course in English

0 Hello there!02br
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00I've just completed an exercise from a book called "A Proficiency Course In English" (Bywater) concerning tenses, and I have some questions about it. Could you give me your explanations? (since the key doesn't say anything apart from giving the answer only)02br
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01b00102b00.01i00 I wonder who 02i01font01i00is making 00/00 was making 02i00that dreadful row00. - are both versions possible? the second one seems a bit odd, especially out of context... to me...02br
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00202b00. 01i00After he 01font00had eaten02font00 an enormous dinner, he fell asleep and was dreaming peacefully when a lump of coal fell on to the heart and woke him up. - 02i00Could you please tell me, why there is past perfect used? Is it necessary here? Could I use simple past? 02br
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00302b00. 01i00I 01font00had been living02font00 / 01font00lived02font00 in that flat for several years before I01font00 decided02font00 / 01font00had decided02font00 to look round for something more central. - 02i00Wchich version is correct? Could I simply use the simple past tense here? We have words like "before" don't we? So is present perfect necessary (especially in the second part) ?02br
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01b00402b00. 01i00I 01font00shall02font00 /01font00 will02font00 01font00have finished02font00 the book in about twenty minutes' time; can;t you wait until then? - 02i00The key gives "shall" and I don't know whether "will" and "shall" differ in any way... do they? Besides, I wanna know whether I could simply say "I will finish the book in about 20 minutes..." and if not, why???02br
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01b00502b00. 01i00The Incas were beaten in battle by the Spanish conquistadores and, after 01font00being held 00/ 01font00were held02font02font00 / 01font00they had been held02font00 in captivity for some time, their Emperor was murdered. - 02i00The key says "had been held" and I have no idea why... couldn't I simply say "were held" ? or "being held" ? why not?02br
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01b00602b00. 01i00Have you seen my glasses? - 02i00Can I say "Did you see my glasses" ? why/why not?02br
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01b00702b00. 01i00When I arrived on the field yesterday, preparations 01font00were02font00 / 01font00had been02font00 in the full swing for the Fair which opens today... - 02i00again, sp vs p. perf. - The key says "were" and I would say "had been" ... is it wrong to use the past perfect here? what would it take to use it? adding a word like "already" maybe?02br
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01b00802b00. 01i00I met your sister yesterday and 01font00I think02font00 / 01font00thought02font00 she 01font00was looking very well02font00 / 01font00she looks very well02font00. - 02i00Can I use simple present? If I mean that she looks fine, like... kind of... generally! And does "thought" imply that I thought that in the past and I don't think that anymore? or does it mean more like "generally" ? Could I use "I think..." here? why not? 02br
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01b00902b00. 01i00Tolstoy 01font00tried02font00 / 01font00had been trying02font00 / 01font00had tried02font00 to educate his serfs but after he 01font00had been working02font00 / 01font00working02font00 / 01font00having been working02font00 at it for 20 years he got discouraged and gave it up. - 02i00Here, I'm completely confused... The key says "tried" and "had been working" ... dunno why... and why the rest is wrong... 02br
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00All the best to you guys! I'm counting on you 05000 Thanks in advance!02br
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00PS. Is that true that if a Brit guy comes to the USA and uses a/the word "fortnight" he may not be understood?02br
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