Translation:I was walking as slow as a snail.
In a free world anyone can use slow as any part of speech, but most people use slowly as the preferred adverb, as this Ngram shows. Hits for slow as an adverb are about 100,000 times less than for slowly as an adverb. I accept that the Ngram corpus may not be representative of the most colloquial of speech, but there is a limit to how colloquial Duolingo can be expected to go
However, I do accept that in some constructions it is a bit more common, and this is one. You can go as slow as... and with other verbs of motion to a lesser degree. This sentence does actually sound fine to me, even though it is quite colloquial.
Which dictionary? Please quote. Including any examples it gives of its use as an adverb.
Just because the dictionary says it is both it does not follow that it can replace slowly in all circumstances.
It is particularly important to know if the dictionary is based on some specific dialect, such as British or American English, and where the quotes come from.
Wiktionary's only attributed quote is from Shakespeare, but it is in verse and the extra syllable would not have fitted in, He was not averse to bending the rules of grammar to fit his metre.
Merriam Webster says only that it is a synonym for slowly, without giving any further information or quotes, whereas for slowly it has the following comment:
Some commentators claim that careful writers avoid the adverb slow, in spite of the fact that it has had over four centuries of usage. have a continent forbearance till the speed of his rage goes slower — William Shakespeare. In actual practice, slow and slowly are not used in quite the same way. Slow is almost always used with verbs that denote movement or action, and it regularly follows the verb it modifies. beans … are best cooked long and slow — Louise Prothro. Slowly is used before the verb a sense of outrage, which slowly changed to shame — Paul Horgan, and with participial adjectives. a slowly dawning awareness … of the problem — Amer. Labor. Slowly is used after verbs where slow might also be used burn slow or slowly and after verbs where slow would be unidiomatic. the leadership turned slowly toward bombing as a means of striking back — David Halberstam.
If we accept that (which is up to us) then we see that slow can be used in this sentence. I think the translation they give is fine as a default, although they should accept slowly as well.
If we accept that it is fine, then the question remains as to how it got so few hits on Ngram. There are two things I can think of. One is that the sort of document that gets into the corpus is using prescriptive grammar, where authors or proofreaders are putting in slowly 'as it is the correct adverb'. The other possibility is that the tagging as faulty - that is the algorithm used to determine what part of speech each word is is failing as it just assumes that slow is by default a adjective. I generally find Ngram pretty reliable, but then I do not usually rely on its tagging. Perhaps it is useless.
I don't have much experience using Ngram, so I can't speak to its accuracy in these matters. I'm certainly not saying that "slow" is just as commonly used as an adverb as "slowly", but I do know that I have heard it commonly used this way (distinctly more than other adjectives incorrectly used as adverbs). When I googled it to see whether this use was standard, the first couple dictionaries I came across confirmed this. The first was from Lexico: "At a slow pace; slowly." I will note that all the examples refer to physical motion. Merriam-Webster simply lists it as a synonym of "slowly". Cambridge defines it adverbially as "at a slow speed". An interesting note is that while "I can't walk any slower" is given as an example without qualification, the example using the base form, "He drives too slow!", is labeled "mainly US". I'm from the US, so that could certainly explain why it sounded perfectly fine to my ears, though I believe the use of "slow" in the sentence in question is in line with the traditionally narrow adverbial use you cited. I certainly would agree that "slowly" should be at least as acceptable.
Interesting. When a dictionary lists something it does not imply how common it is. So it just means it is found occasionally. As for the slower example (and the one I gave), we will discover later that Gaelic does not add gu to comparatives or superlatives at all, and it is quite plausible that this can happen to some extend in English. Indeed this is my experience, so I think the slower example is totally irrelevant.
The suggestion that the other example is predominantly American is interesting, as it is the first suggestion of any regionality, but again, the adverb too is something which would cause the gu to disappear in Gaelic.
In fact all the dictionaries are struggling to find examples that would contain gu in Gaelic - i.e. without -er, -est, more, most, so, very, as, too, etc. Would you ever use it without any of those things?
I think we all accept that slowly is an acceptable answer. The problem is that no one will fix this, or can be expected to fix it, until someone reports this as a 'my answer should be accepted'.
I think the mods tend to read pages they have already commented on, but as no mod has commented here they will not see this until it is reported.
Good question. You are one of the people that the quote below classifies as 'hawk-eyed'
Hawk-eyed learners among you may notice that the word bròg has been slenderised to bròig. We do not go into the grammar as to why this happens here (didn't want to rush it), but the change is caused by an aspect Gaelic's dative case.
Because they don't want to rush they actually list both forms of seilcheag in the vocab in the notes, so they want to accept it for now and learn about it later.
If you can't wait, here is a brief summary, although it relies on quite a lot of grammar that you may or may not know:
- We know that seilcheag is feminine singular because of the -(e)ag ending.
- The preposition ri takes the dative case.
- Feminine singular nouns (only) slenderize in the dative.
- -eag slenderizes to -eig.
So four rules all coming together. You will learn each of them in due course. But the best way to learn is the way children do. Just get used to it and eventually you will know what sounds right. That's why they are quite happy to give you an example long before they teach the rules.