"Tongs" are a device for grabbing something. You often see them used as serving utensils for tossed salad and other foods: https://www.google.com/search?q=tongs&tbm=isch Since a tong by itself would not be that useful, they come in pairs, which is why the plural "tongs" is typically used. In the USA and Canada, a "tong" is also a gathering place of Chinese immigrants who belong to a secret society or some group with illegal activities. The vast majority of Americans are unaware of this meaning. There is also the very similar word "thong", which was generally thought of as meaning a special kind of sandal: http://www.souvenirsaustralia.com/images/thongs.jpg As you would expect, thongs come in pairs, so the plural is typically used. Also, many of the older generation lament that the word "thong" has become more commonly understood to mean very scanty underwear worn by women, and worse, by men. Sorry, no hyperlink for that one! I do not recall hearing "donk" in the USA. However, the word reportedly has several meanings in the UK and Australia: http://en.wiktionary.org/wiki/donk Also, the word appears to mean someone who plays poker very poorly, and it can be used as a verb, as in hitting someone. However, if you use "donk" in the USA, most people will have no idea what you're saying.

Correct sentences: "What do they mean?" "What is their meaning?" It's actually hard to say without context. Do you have a full sentence? "Tongs" could mean forceps (maşa)... I'm pretty sure you didn't misspell "tongue" ;) Medical donks? No idea. Unless it's a type of car? http://jalopnik.com/5974931/your-guide-to-the-worlds-most-hated-car-culture-donks Maybe because you wrote "medical", I'm thinking of surgical tools.

Thanks

No sorry, that sentence is not correct.

Also can i ask that question " what do their means " ?