 Punctuation consists only of a period, written as a small horizontal segment on the base line, because the dot, comma, question mark, exclamation mark, and others, have special meaning and could be confused with words.Colons and double quotes are acceptable, especially for beginners.Digits are similar to the Arabic numerals, except for 5 and 7, which can be written without a horizontal bar; also, special notation is normally applied for hundreds, thousands, and millions.