Final answer:
The use of 'gonna' instead of 'going to' demonstrates a problem of informal language or colloquialism in English grammar.
Step-by-step explanation:
The substitution of 'gonna' for 'going to' exemplifies colloquialism in English grammar. This informal expression is part of everyday spoken language but may be considered nonstandard in formal writing or communication.
Colloquialisms like 'gonna' arise from the natural evolution of language in casual conversation, reflecting an ease of expression. While widely accepted in spoken communication, adhering to formal grammatical structures is essential in more formal contexts.
Recognizing when to employ colloquialisms is crucial for effective communication, as their use can convey familiarity or informality, but they may be inappropriate in certain professional or academic settings.