Polygonia comma form of comma is frequently confused with the dark form of the question mark ("P. interrogationis"), but the two can readily be distinguished by the shape of the comma mark on the underside. The pale form is easily confused with the satyr comma ("P. satyrus"), which usually occurs north and west of the eastern comma's range. They can be distinguished by the upperside color, which is orange brown in the comma and tawny yellowish brown in "P. satyrus"; by the underside pattern, which tends to be mottled in the comma but appears to be more longitudinally streaked in "P. satyrus";
Punctuation of English their cover letters. In contrast, closed punctuation uses commas and periods in a strict manner. Closed style is common in presentations, especially in bulleted and numbered lists. It is also frequently used in advertising, marketing materials, news headlines, and signage. The approximate average frequencies for English punctuation marks per 1000 words based on 723,000 words of assorted texts are as follows (as of 2013, but with some text corpora dating to 1998 and 1987): The apostrophe , (sometimes called inverted comma in British English) is used to mark possession as in ""John's book"", and to mark letters omitted in contractions,