Huomasitko, miten hyvin rumpali piti tahdin?

It turns the verb into a yes/no question.

• huomasit = you noticed
• huomasitko = did you notice?

Finnish usually does this by attaching -ko/-kö to the first important word in the sentence, often the finite verb.

Because Finnish does not use a separate auxiliary like English do/did in this kind of question.

English:

• Did you notice ... ?

Finnish:

• Huomasitko ... ?

The past tense is already inside huomasit, and the question marker is -ko.

Because the sentence asks whether the listener noticed something that happened earlier.

• huomaat = you notice / you are noticing
• huomasit = you noticed

So Huomasitko ... ? means Did you notice ... ?

Finnish often leaves out subject pronouns when the verb ending already shows who the subject is.

• huomasit already means you noticed

So adding sinä is usually unnecessary unless you want emphasis or contrast.

For example:

• Huomasitko? = neutral
• Sinäkö huomasit? = Was it you who noticed? / extra emphasis

The comma separates the main clause from a subordinate clause.

• Main clause: Huomasitko
• Subordinate clause: miten hyvin rumpali piti tahdin

That second part works like what you noticed. In English, this is similar to:

• Did you notice how well the drummer kept time?

Finnish normally uses a comma before this kind of subordinate clause.

It means how well.

• miten = how
• hyvin = well

Together, they introduce the subordinate clause:

• miten hyvin rumpali piti tahdin = how well the drummer kept time

This is not a separate direct question. It is part of the larger sentence after Huomasitko.

Yes. Miten hyvin and kuinka hyvin can both mean how well.

In many contexts:

• miten hyvin = very common, natural
• kuinka hyvin = also correct, sometimes a bit more formal or stylistic depending on context

So Huomasitko, miten hyvin... is completely normal Finnish.

Because hyvin is an adverb, and it describes how the action was done.

• hyvä = good (adjective)
• hyvin = well (adverb)

Here it modifies the verb piti:

• piti tahdin hyvin = kept time well

So hyvin is the correct form.

Because rumpali is the subject of the subordinate clause, so it is in the nominative singular.

• rumpali = drummer

Finnish also has no articles, so rumpali can mean the drummer or a drummer, depending on context. In this sentence, English naturally uses the drummer.

Yes, pitää has several meanings in Finnish. Here it means something like to keep / maintain, in the expression pitää tahdin.

So in this sentence:

• pitää tahdin = keep time / keep the beat

And piti is the past tense, because the sentence is talking about what the drummer did.

So:

• rumpali piti tahdin = the drummer kept time

This is a good reminder that Finnish verbs can have several meanings depending on context.

Because tahdin is the object form used here.

The dictionary form is:

• tahti = beat, tempo, time

In this sentence, it appears as:

• tahdin

This is a singular total object form. In practice, for learners, the important thing is that many Finnish objects in affirmative sentences appear with an -n ending like this.

So:

• tahti → tahdin

Here it is the thing being kept:

• piti tahdin = kept the beat / kept time

Not in the same way as the whole sentence.

The whole sentence is a yes/no question:

• Huomasitko ... ? = Did you notice ... ?

Inside it, miten hyvin rumpali piti tahdin is an embedded how-clause. It tells what was noticed.

So the structure is roughly:

• Did you notice
  • how well the drummer kept time?

Only the whole sentence is being directly asked to the listener.

Somewhat, yes, but the given order is the most neutral and natural.

Neutral order:

• Huomasitko, miten hyvin rumpali piti tahdin?

Inside the subordinate clause, Finnish usually keeps a fairly straightforward order:

• rumpali = subject
• piti = verb
• tahdin = object

If you change the order, you may create emphasis, contrast, or a more marked style. For a learner, the original word order is the best one to copy.

Here they are:

• huomasitko → dictionary form huomata = to notice
• miten = how
• hyvin → dictionary form hyvin = well
• rumpali = drummer
• piti → dictionary form pitää = to keep / to hold / to like / must, depending on context
• tahdin → dictionary form tahti = beat, tempo, time

This is useful because Finnish words often appear in forms that look quite different from the dictionary form.