"This TV is old."
It should be "です" not "でず". Probably just a typo, but just to make it clear to other people.
Am i missing something, or do they quiz us on new words without actually teaching them first? I'm using the Android version, if that makes a difference.
That's the way DuoLingo works. You just have to tap on the word to see the translation. That's how it teaches you the new words.
Not always the translation helps. I feel like the whole Japanese course is a guessing game sometimes. It's ok though.
Don't I seem to be rude or impolite not sounding the ending "desu"? Like in here: "このテレビはふるい". To what degree is it essential for peaceful and quiet friend-like chatting?