A note on the English:
The present tense "I read the book" has identical spelling to the past tense "I read the book". The difference is in the pronunciation. The present tense sounds like "reed" while the past tense sounds like "red". But actually using "red" as the past form of "read" is incorrect.
Present = "read" ~reed
Past = "read" ~red
the same with "a lot of".
I suppose, perfect should be accepted in English.
There is no strong rule to translate "Praeteritum" as "past simple" and "Perfekt" as "perfect". How I know.
And "present perfect" makes more sense than "past continuous" in this case. Doesn't it?
On the contrary, there is no real difference in meaning between preterite and perfect. The difference you mentioned exists in other languages, but the main difference in German is that preterite is mostly used in writing while perfect is used in speech. "Have read" is a perfectly good translation, even if Duo doesn't accept it.
That link very vague (both in English and in German), I wouldn't use it as reference.
The Präteritum makes actions feel remote, suggesting that the action's exact time is not primary concert. That's why it's the primary choice when it comes to literature and novels.
The Perfekt shows that a past action has some impact on the present. Since is the nature of the things we mostly talk about, in spoken language this makes up the vast majority of the past tense cases.
One can't simply say that "this is for spoken language and that is for writing". The difference is their function. The choice is driven by this function and not the other way around. There is Präteritum in spoken language, so is Perfekt in literature - whenever it's necessary.
I'm not sure why you say that link is vague, but here's a better one (written by a native German speaker).
That idea of remoteness may have existed in earlier forms of the language (as well as in English), but the main distinction now is spoken vs. written. Many Germans themselves refer to them as spoken and written past. Sure, there are exceptions (like modal verbs), but for the vast majority of verbs preterite is used in writing and perfect in speech.
@Karcsibacsi While a distinction between preterite and perfect certainly exists―although the line definitely blurred―my experience is that they are mostly only preserved in written German (unless hypercorrection forces a preterite where a perfect would have been appropriate anyway), otherwise preterite or perfect is a matter of idiomatic usage rather than difference in meaning. Your example seems to disprove this, but may I ask: where are you from? Could it be a regional variation?
I wouldn't put too much faith in grammar books either: they tend to be prescriptivist ignoring overwhelmingly common usages and sometimes making up straight up (but I believe well-intentioned) lies: it is famously the case with English, where grammarians introduced rules from Latin de novo, and in the―alas, likely misattributed―words of Winston Churchill: "this is the kind of nonsense up with which I will not put" (which incidentally misapplies the already false rule: up can be an adverb, the prescribed form would be "with which I will not put up", which is also correct). Sentences can end with prepositions, infinitives can be split, and a sentence can begin with "but" (whether it is poor style is a different matter).
That said, German is a polycentric language, and regional usage differences are to be expected in any respectable language, so I think trying to find the definitive answer to the problem of the German past is ultimately pointless, and may in any case very well change in the next few years or a few kilometres from here or there.
Let me start with a few more examples: This first one applies both to spoken and written German: Ich schlief schlecht. -> I had a bad sleep but it has no effect on my present contidion. Ich habe schlecht geschlafen. -> I had a bad sleep, I'm tired now and can't work properly
These are out of my language book.
One more from written German: Ich antworte sofort, wenn ich deinen Brief bekommen habe. In this case it's an action that will be completed in the future. This is not spoken German. What we aim here is a specific function, so we choose Perfekt, even if it's in a book.
That link.. :D If there's any conflict between my grammar book (from the 90s) and a website written in the style of a stand up comedian, I have to side with the grammar book.
I accept your point if you want to learn that way.
Past tense. Although "We read many books" is an ambiguous sentence when read out of context in English, this sentence appears in the 'simple past' lesson so you should interpret it that way.
It seems that in the meantime, Duolingo now uses "We were reading many books" as the preferred translation, although the German sentence doesn't strictly keep that past-continuous tense.
German has two past tenses, the perfect ("haben gelesen") and the preterite ("lasen"), and they mean essentially the same thing-- they cover all senses of the past tense ("read," "have read," "were reading"). The main difference is the perfect is mostly used in speech while the preterite is mainly for writing.