German phrase
Das geht bestimmt schief.
Meaning
That will definitely go wrong
When to use it
It means you expect failure. Use it when you think something will not work.
Example dialogue
Ich muss gleich vor der Klasse vorlesen. Das geht bestimmt schief.
I have to read aloud in front of the class soon. That will definitely go wrong.
Keine Angst, ich sitze neben dir.
Don't worry, I'll sit next to you.