Interesting that he used colloquial language texts first and did the translations all by himself. Today it is very tempting to just translate from L2 to L1 with the help of Deepl thus skipping the desirable effort of working through the text with your own brain.
Together with David Allen Martin (Translation Cubed) we now find two of the major teaching polyglots using this method.
How I Learned 10+ Languages with the BDT
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One day, my parents hired an English tutor to come and work with me at home. This tutor taught me that language was not just some boring school subject, but rather a means to learn about and explore all sorts of interesting things, like movies, books, and—of course—people! This began my fascination with using natural, authentic language content to learn languages. This fascination would eventually lead me to the epiphany that would help birth the Bidirectional Translation method!
One day, I decided to start learning German on my own. As much as I liked authentic content at the time, I had no idea how to start learning German that way. So, instead, I went the traditional route, and tried to learn the language the old-fashioned way, using dictionaries, and an old grammar book. Boring!
Eventually, I became so disillusioned that I nearly gave up. Fortunately, before that could happen, I stumbled upon a commercial for a German course on audiocassette which claimed to teach the language using natural, authentic dialogues, spoken by real Germans. Eureka! This was just the kind of interesting and natural language content I needed to get started as a beginner. These dialogues represented German as it was spoken in real life, so they were infinitely more interesting than any verb tables or word lists.
As I went through the content day after day, I noticed something interesting: if I took the German dialogues and translated them into Italian, I could memorize words and phrases much more easily. Better yet, if I translated my Italian translation back into German a few days later, I ended up remembering even more!
Gradually, I found that this system of taking natural dialogues in German and translating them in two directions wasn't just helping me remember words and phrases—it was helping me think in my target language! Following this system, I went through every single German dialogue available in my audio course. Within a year and a half of starting German, I found that I was able to have natural, comfortable, and confident conversations with German people.
At the time, I was worried this could have been a fluke. So I decided to try it again, but this time with Spanish.So I purchased a Spanish audio course, and applied my new bidirectional translation method to it. Sure enough, I reached fluency within one year!
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