What is the meaning of the hidden test cases in code coach

Answer 1

That was right tnx

Answer 2

Now i know that at least one of the hidden test case might be grammar

Answer 3

Here is my code in the jungle camping test
animal = {
"Grr" : "Lion",
"Rwar" : "Tiger",
"Ssss" : "Snake",
"Chirp" : "Bird"
}
animal_sound = input(" ").split(" ")
output = " "
for i in animal_sound:
output += animal[i] + " "
print(output)
I don't know why it doesn't work