Comma titles that follow a name: "John Smith, Ph.D." Similarly in lists that are presented with an inversion: "...; socks, green: 3 pairs; socks, red: 2 pairs; tie, regimental: 1". Commas may be used to indicate that a word, or a group of words, has been omitted, as in "The cat was white; the dog, brown." (Here the comma replaces "was".) Commas are placed before, after, or around a noun or pronoun used independently in speaking to some person, place or thing: In his 1785 essay "An Essay on Punctuation", Joseph Robertson advocated a comma between the subject and predicate of
Punctuation to be more prominent) by using not differing height but rather a differing number of marks—aligned horizontally (or sometimes triangularly)—to signify a pause's value: one mark for a minor pause, two for a medium one, and three for a major. Most common were the "punctus", a comma-shaped mark, and a 7-shaped mark ("comma positura"), often used in combination. The same marks could be used in the margin to mark off quotations. In the late 8th century a different system emerged in France under the Carolingian dynasty. Originally indicating how the voice should be modulated when chanting the liturgy, the "positurae"