"The big one is not bad!"
Translation:Ta velká není špatná!
It looks to me like the gender in the sentence (velká and špatná) would in real life give the sentence context. It accepted my answer of "to velké není špatné" too. German does a similar thing of using gender in demonstrative pronouns to make it obvious what you're talking about, without using the need for the english "one" pronoun.
Example: I'm telling my friend his cake is good, (a masculine object in German)
"Der ist ganz gut. Wie hast du den gemacht?" (The -- is quite good. How did you make him?)
¯_(ツ)_/¯ This sort of stuff helps me anyway!