Whether you are analyzing a hacker's intercepts or decrypting a secret file, you will frequently need to describe how easy or difficult a code is to crack.
The Prefix "auð-" (Easy to)
To express that an action can be done easily, Icelandic uses the prefix auð-. By attaching it to the front of a past participle, you create an adjective meaning "easily [done]" or "easy to [do]".
For example, combining auð- with séður (seen) gives you auðséður (easily seen).
The Prefix "tor-" (Hard to)
Conversely, when something is difficult to accomplish, use the prefix tor- ("with difficulty" or "hard to").
Attaching it to the past participle skilinn (understood) creates torskilinn (hard to understand).
Adjectival Agreement
Because these combined words function as adjectives, their endings change to agree with the noun they describe in gender, number, and case.
Notice how the masculine form auðleystur (easily solved) adapts to the neuter form auðleyst to match the neuter noun vandamálið (the problem):
You can apply these highly productive prefixes to almost any past participle to describe the difficulty of a task.