Grammar question - wouldn't the accusative indicate that you started to study "last week" (as in, started studying the events that took place during that time frame)? I would expect an adverb in order to express the time frame when the starting happened. "Mi komencis studi Esperanton laste semajne." But then, I'm just coming back to the language from a decades-long lapse.
You asked four months ago but have a five-month streak, so here's my answer:
You are almost right, it should be “lastsemajne.” “Laste semajne” could be more or less “lately weekly.”
And yes, ambiguities between a direct object in accusative and a time specified by an accusative may occur. “Esperanton” is obviously a direct object but with “lastan semajnon” (Andi M's answer) it's more difficult to distinguish between
- I started studying last week (adverbial expression)
- I started studying the last week (object; I now study everything that happened during that week – maybe for a thesis ☺)
In practice I have noticed that many speakers distinguish these cases like in English, by using or omitting the definite article: “(la) lastan semajnon”. PMEG, 12.2.4., however, does not mention such a distinction. So for understanding you depend on context and meaning.
When using the language actively you can avoid such ambiguities by indicating time with a preposition, such as en or je:
- Mi komencis studi en la lasta semajno.
- Mi komencis studi je la 15-a de decembro (tago de la libro).
The sentence is a question, and English uses “to do” for questions without another auxiliary verb. So it's “did you start” instead of “started.”
Please do not ask me “why.” The vast majority of speakers use it like that, so maybe it's all about the “normative power of the factual?”
is not "when did you begin to study Esperanto" a reasonable translation?
Vi pravas per “pli bone malfrue ol neniam.” ☺ ☻
If by “manieron tro malfrue” you mean “way too late,” that is an anglicism that cannot be translated directly. Possible translations of “way too late” are
- multe tro malfrue
- ege tro malfrue
- multege tro malfrue
“maniero” can mean “way” in sentences like
- la plej bona maniero lerni = the best way of learning
- mi ne scias alian manieron fari tion = I know no other way of doing that
When I read this, it feels like an incomplete dependant clause: "When you began to study Esperanto..."
For example, I expect it to continue with something like "... you only knew your native language."
I understand that it's a question, but it has me wondering: how would I construct the above dependant clause if not with these words?
EDIT: I replaced incorrect uses of "prepositional phrase" with "dependant clause".
You would use exactly the same wording – followed by what would then be the main clause:
- Kiam vi komencis studi Esperanton, vi sciis nur vian denaskan lingvoon.
In speech, stress or intonation may vary a bit. For instance, some people might stress the word “Esperanton” here, to emphasize the contrast to “your native language.” But that is a minor matter.
I have never found that to cause confusion in practice.