Rule 1 — When the conjunction is omitted between the members of a compound sentence, they should be separated by semicolons.
Example : The blue sky now turned more softly grey; The great watch-stars shut up their holy eyes; the east began to kindle.
Note 1 — When the sentences are short and very closely connected, they should be separated by commas ; as, "The fire burns, the water drowns, the air consumes, the earth buries."
Rule 2 — When the members of a compound sentence are subdivided by commas, they should be separated by semicolons.
Example : Under the fierce winds, the pines bend their heads; and the mountain snow is swept away, forming immense heights, and hiding everything from sight.
Rule 3 — The expressions namely, as, i. e., or that is, viz., etc., should be preceded by semicolons and followed by commas.
Examples : We have five senses; namely, sight, taste, hearing, smell, and feeling.
Rule 4 — When several expressions have a common dependence on a principal element, they should be separated from one another by semicolons.
Examples : If we think of glory in the field ; of wisdom in the cabinet; of the purest patriotism; of the highest integrity, public and private; of morals without a stain; of religious feelings without intolerance and without extravagance, the august figure of Washington presents itself as the personation of all these.
When the element upon which the several expressions depend comes at the beginning of the sentence, the expressions should be separated from it by a comma; when it is placed at the end of the sentence, it should be separated from the series by a comma and a dash; as, "Science declares, that no particle of matter can be destroyed ; that each atom has its place in the universe ; and that, in seeking that place, each obeys certain fixed laws."
Uses of Semicolon in Business Letters :
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