What a great sci-fi story.

[Silverobama]

Last night, I wrote down five words and asked my cousin to make up a story (by using those words) and he wrote “A giant grape saved the people in an airplane by stopping the time and then let them safely land on the ground”. I commented “Wow, what a great sci-fi story”.

Is my comment natural?

 

[emsr2d2]

Last night, I wrote down five words and asked my cousin to make up a story (by using including those words). and He wrote “A giant grape saved the people in an airplane by stopping the time and then let helped them safely land on the ground”. I commented “Wow, what a great sci-fi story”.

Is my comment natural?

Your italic comment is natural, although I'd probably call it "fantasy" rather than "sci-fi". A giant grape doesn't make me think of outer space. Please note my corrections to the rest of your post. Out of curiosity, what were the five words you gave your cousin?

 

[Silverobama]

Out of curiosity, what were the five words you gave your cousin?

Airplane, grape, ground, giant and people.

although I'd probably call it "fantasy" rather than "sci-fi".

I wonder if my whole sentence is natural with "fantasy".

Wow, what a fantasy story!