Complex sentence: A naive English speaker could correctly infer that someone who is "inarticulate" is not articulate but would be incorrect in saying that something "invaluable" is of little or no value.
Split into simpler sentences: A naive English speaker could correctly infer that someone who is "inarticulate" is not articulate. The same speaker would, however, be incorrect in saying that something "invaluable" is of little or no value.