Translation:That blouse is very cute, isn't it.
"That blouse is very cute, right?" is now accepted 20180919.
"ne" is not always used to request confirmation. It depends on whether a question mark or period follows it. While talking, it depends on tone.
"ne?", high pitch - requesting confirmation, like "this is the right button to push, right?"
"ne.", low pitch - rhetorical question, not requesting confirmation, like "isn't that a lot of buttons to put in a room."
I think that duolingo is better to practice, for people that already know some Japanese, or are learning the basics with another way. In fact, as no grammar is explained in duolingo, you need to find it on your own.
There is no magic trick to learn a language but too practice so this app is not that bad. :)
It's because the system of この/その/あの doesn't exist in English. その just means it's closed to the listener, nothing else. Only real experience make you understand those differences. And it's not a problem if you can't "know" if it's the or that, it doesn't exist in Japanese and you can never translate a language directly. :)
How about some content for the guys in this lesson, just to break up the monotony?
Here's one for free:
"Bro, I got this gallon of engine grease on sale for 850 yen."
Or maybe something along the lines of:
"Big brother, be careful with that 1 watt laser that you bought in Akihabara."
Corrections to my 日本語 are welcome.