"That watermelon is fresh."
This says "That watermelon is very fresh," while the question asked me to translate "That watermelon is fresh." Inclusion of the word "hen" before "xiaxian" means "very fresh" rather than just "xiaxian," or "fresh."
很 can also be used to connect the subject with the adjective, not always means “very”. Did you take a quick test without learning the basics?
Not really though. Adjectives have to take a modifier of some sort which most typically is 很. Therefore, it rarely ever translates to very. Just think of it this way: 是 is for nouns, 很 is for adjectives.