Hello, I have 2 sentences. I translated them. But where is the "speek" word? Why google translate dont use "sprechen"?
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Languages have different, in some cases extremely different, grammar. Machine translations started with literal word-by-word translations, which are extremely bad for this reason. As machine translation algorithms evolved, they became better and better at producing translations with correct grammar. However, the translations still often did not appeared idiomatic to native speakers because often one of several valid choices is preferred by them and this choice can be quite different between languages. Modern machine translation tries to solve this (I believe by utilizing a text corpus). As a result you won't necessarily find a literal translation of each word from the original phrase in the translation.
"Ich kann Türkisch sprechen." is correct grammar but apparently judged not idiomatic by the Google algorithm (this could change with context). In German, we tend to say "Ich kann Türkisch." or "Ich spreche Türkisch.", the latter being preferable, in particular in more formal speech.
I can't comment on Google algorithms more specifically.
Part of OP's confusion probably stems from the fact that the English verb can can only be used as an auxiliary verb. The German congnate können can also be used as a an auxiliary verb and can can almost always be translated with können. However, können can also be used as non-auxiliary verb, so können cannot always be translated with can.
In Ich kann Türkisch. kann is used as a transitive verb. This is the 3rd meaning listed in the Wiktionary page on können. There is no equivalent meaning of can in English.
As @Roland pointed out, Ich kann Türkisch sprechen. is grammatically correct, but not idiomatic in German. But the more idiomatic Ich kann Türkish. can be tricky to parse for an English speaker since I can Turkish. is not only unidiomatic, but also grammatically incorrect in English.