Snellen chart H, K, O, S, 3, U, Y, A, C, E, G, L, 2. The normal Snellen chart is printed with eleven lines of block letters. The first line consists of one very large letter, which may be one of several letters, for example E, H, or N. Subsequent rows have increasing numbers of letters that decrease in size. A person taking the test covers one eye from 6 metres or 20 feet away, and reads aloud the letters of each row, beginning at the top. The smallest row that can be read accurately indicates the visual acuity in that specific
Four-letter word Four-letter word The phrase four-letter word refers to a set of English-language words written with four letters which are considered profane, including common popular or slang terms for excretory functions, sexual activity and genitalia, terms relating to Hell or damnation when used outside of religious contexts or slurs. The "four-letter" claim refers to the fact that a large number of (but not all) English "swear words" are incidentally four-character monosyllables. This description came into use during the first half of the twentieth century. Common four-letter words (in this sense) that are widely considered vulgar or offensive to a notable degree