Here's the answer:
“すごく便利なカードです”
(sugoku benri na kādo desu)
Watch a real native speaker say it:
Here's how it sounds in a textbook:
You could also say:
- とても便利なカードです
- すっごく便利なカードです
Fun fact: the hundreds of thousands of people learning Japanese with Memrise get this phrase correct 95.42% of the time!
