This is the 18222nd most frequent Russian word.
четким
Clear, precise, or sharp.
As an adjective, 'четким' describes a clear and precise attribute of the plan discussed.
Этот план оказался достаточно четким.
This plan turned out to be clear enough.
Here, 'четким' emphasizes the improved clarity and legibility of handwriting due to effort.
Его почерк стал намного четким благодаря практике.
His handwriting has become much clearer thanks to practice.
In this context, 'четким,' related to the voice, highlights precise and understandable articulation.