"I already have such a table" would be good English idiom for this construct. Duo suggests "such" in the hints, but since the hints are not reliable, I can't say whether Duo would accept this translation. Still, the translation I've given expresses the idea in good idiomatic English.
Pronouncing English "t" with my tongue on my teeth, I think I can see your point. I doesn't sound like a "th" to me but it feels almost identical to English "d", the difference being tiny. Is that how "т" should generally be pronounced? And if so, is there no direct equivalent to the English "t"?
Don’t trust me to 100 %, I generally think I do have a good pronunciation of Russian, I am not a native speaker, so I might be mistaken. I‘m only half-Russian. ;)
In Russian, the letter Т is pronounced somewhere between a ‘normal’ alveolar [t], like in English, and a dental [t̪]. I would have said that it is denti-alveolar, being pronounced somewhere in between your teeth and the alveolar ridge.
No, there‘s no direct equivalent in English, unless count dialects. If you live in India, southern Ireland or in Dublin, this is how you would pronounce your normal th, like in ‘thin’. If you live in Ulster, this is how you would pronounce the t i ‘train’ or ‘truck’. Where do you live, by the way? There’s a pretty long list here on Wikipedia about where this dental [t̪] occurs, so maybe I can give you an example from your native language? For me, it‘s the T in the Swedish word tåg.
That is interesting. It hadn't really occured to me that there can be so many ways of pronuncing a "t". My native language is Danish and, when I say English, I mean the Standard English variants as heard from CNN and BBC reporters, Cameron, Obama ect. As far as I can see from the list, this sound is also unknown in Danish and German, explaining my confusion. That the Swedish "t" is different from the Danish surprises me a great del.
Besides the point given by R_Andersson, there’s also the fact that the English and Danish initial "t" is aspirated (i.e. pronounced with a slight puff of air, as if there was an "h" after it), and the Russian "t" is not aspirated, which may make it sound closer to "d" to you. Same applies to p~b, k~g.
I happened to be reading a bit about the Maori language on Wikipediatoday and, apparently, English speakers hearing an unaspirated P as a B and an unaspirated T as a D is a phenomenon that also occurs between speakers of English and Maori. As Gwenci pointed out above, these stops are pronounced like aspirated consonants in Danish and English when in the begging of a word, this is not the case for Maori. Interesting!
‘Because English stops /p, t, k/ primarily have aspiration, speakers of English often hear the Māori nonaspirated stops as English /b, d, g/. However, younger Māori speakers tend to aspirate /p, t, k/ as in English. English speakers also tend to hear Māori /r/ as English /l/ in certain positions (cf. Japanese r).’