Shadowing is a technique popular at Japanese junior and senior high schools for learning English. It's also effective going the other way.
Basically, in shadowing, you simply find audio material in the source language, play it back, and repeat it as you go along. It's not the most exciting process in the world, but it has several benefits:
- You are forced to speak at natural conversation speed. Since you are following a native speaker, you have to keep up.
- You learn to mimic intonation. Intonation is one of the hardest things to master when studying by yourself. Especially for English speakers learning Japanese, "flattening out" your natural tendencies to stress what you want to emphasize is critical to sound more natural in the language.
- You start to pick up phrases rather than just vocabulary. Repeating what someone has just said requires you to listen for and process phrases rather than just individual words. In my mind, this is a far more effective approach than traditional vocabulary tapes.
What makes for good shadowing material?
First, this may go without saying, but it's important to have material that you already understand. If you don't understand the words being said, it doesn't make much sense to mindlessly repeat them. (This applies to junior high students as well.)
Ideally, if what you're listening to has visuals, you can get subtitles. However, many supplied subtitles don't always match what is being said exactly, so sometimes these can be more of a hindrance than help.
Personally, I recommend the following:
- NHK news- As long as you live in Japan and have a TV, NHK has morning and evening programs that always include complete subtitles. The announcers also speak relatively slowly so they are easier to follow than other news programs. Also, as a government new agency, only standard, sterile Japanese expressions are used, which makes it good practice for business.
- TV dramas- If you're more interested in improving daily conversation, focusing on Japanese TV dramas (or US shows dubbed into Japanese) is a good start.
- Podcasts- If you don't have access to Japanese TV, podcasts (iTunes allows you to download thousands for free) can be a decent replacement.
I would avoid anime for shadowing, simply because the language used in such shows is often wildly exaggerated and totally inappropriate for any normal use. For the same reason, jidaigeki (samurai period dramas) is best avoided.
As with all language studying, the secret here is consistent practice. A few days of shadowing won't do much for you, but if you spend 15 minutes a day for a month or two, you will start to see measurable improvements.