Ni / o / particles

Hello everyone,

In lesson 1.9, we're given three examples of how long it takes someone to do something.  There isn't really any explanation as to why に in the first example,  を in the second example, and nothing in the third example is used.  I'm still having a terrible time understanding when to use を, and when the honorific お is used, but this has separately confused me even more.  

どれ　ぐらい　にほん　に　たいざい　して　います　か？
How long have you been staying in Japan? / Dore gurai nihon ni taizai shite imasu ka?

どれ ぐらい ピアノ を れんしゅう して います か？
How long have you been practicing piano? / Dore gurai piano o renshū shite imasu ka?

どれ ぐらい りょこう して います か？
How long have you been traveling? / Dore gurai ryokō shite imasu ka?

Is thing something that is explained in detail in a further lesson?

Thank you!!!

The different particles are used because they're answering different questions. The construction taught in the lesson is: どれ ぐらい …~て います か？/ How long have you been 「verb (-ing)」?

にほん に answers where— How long have you been staying in Japan?

ピアノ を answers what—How long have you been practicing piano?

The third question does not ask for such specifics (for example How long have you been traveling by foot?)
 

Oh, I see.  Hmm, I did not look at the sentence structure in such a way (answers "what" and answers "where").  I'm now seeing some logic here.

Thank you so much...  sigh.

If you want to think of the wo を　particle more then think of sentences like this

ステーキを食べる sute-ki wo taberu
水を飲む mizu wo nomu
ハイキングをする haikingu wo suru
日本語を勉強する nihongo wo benkyou suru

Ryokou 旅行する is different as it is implying something you are presently doing where as the piano question is asking how long you have been doing something over a period of time.

Thank you Tony.  That subtle difference (presently doing vs. doing something over a period of time) wasn't something that clicked with me when I was trying to understand the difference.

I"m sorry, along the same vein, I have another question.  When we say the sentences:
にほんご　が　はなせます 
にほんご　が　はなせます　か？

In the module, the following example is given:
はい、すこし はなせます 

Is the reason the  が is omitted because the topic is already being discussed, and so the response is more informal?
はい、すこし が  はなせます

Thanks so much!!
 

Hi イリニさん!

「すこし」is not the topic of that sentence. 「すこし」means a little, so it is determining/describing the amount of Japanese that person speaks.

The omitted topic of that sentence is 「にほんご」. So, if we write out the full sentence, it would be:

「はい、にほんご　が　すこし　はなせます。」

Hope that helps!

Crystal