yes they are synonyms. They're really the same thing, except refering to someone as being 'chatty' is more informal and coloquial
Very informal
An informal writing style in nonfiction would typically include a conversational tone, the use of contractions, personal pronouns (such as "I" and "we"), and a more relaxed approach to grammar rules. It often aims to engage readers in a friendly and approachable manner similar to a casual conversation.
An informal tone is when you speak to someone, like a friend, when having a normal everyday conversation with them. You are speaking to them in a friendly manner.
we're going to have an awesome time.
Informal but firm (APEX)
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The letter written in Option B has the most informal tone. It includes contractions, slang, and a relaxed writing style.
Essays can be either formal or informal, depending upon your intended readership. ____ False. It totally depends on the type of essay. Personal essays, for instance, often use the informal tone... and the tone should match your audience in any case.
You should avoid slang and informal tone.
Formal, normal, and informal
informal