must have an wrong impression of fluency

[Silverobama]

In a public chat room (where people can send audio messages so that others can hear your voice and what you say), A was keeping talking. He spoke very fast but what he said contained a lot of grammatical errors. Then someone commented "Wow, his English is fluent".

I replied "You must have an wrong impression of fluency". Is this sentence natural? The intended meaning is "I think you totally don't know what fluency means because A doesn't speak fluent English at all".

 

[Skrej]

"You must have an a/the wrong impression of fluency". Is this sentence natural? The intended meaning is "I think you totally don't know what fluency means because A doesn't speak fluent English at all".

With the noted article correction, it's okay. I'd say the definite article is more common, but an indefinite article would still work. However, you surely know that 'an' is only used before initial vowel sounds.

 

[Silverobama]

With the noted article correction, it's okay. I'd say the definite article is more common, but an indefinite article would still work. However, you surely know that 'an' is only used before initial vowel sounds.

Much appreciated. How would native speakers express this idea, may I ask?

 

[emsr2d2]

I'd say something like "We must have different definitions of fluency!"