Semicolon Before Conjunctive Adverbs and Transitional Expressions
The Semicolon
Rulebase Summary
In a compound sentence, use a semicolon before the second independent clause when it begins with a conjunctive adverb or transitional expression such as however, therefore, consequently, furthermore, moreover, nevertheless, indeed, in fact, namely, on the contrary, or similarly. Follow the transitional word with a comma.
Exception: the words hence, so, thus, and yet are no longer set off by a following comma.
Important: if the transitional expression merely interrupts one clause (rather than introducing a second independent clause), set it off with commas instead — no semicolon.
Examples
A. I filed the report on time, however, the supervisor never reviewed it.
A. I filed the report on time; however, the supervisor never reviewed it.
Semicolon before 'however'; comma after it.
A. The contract was valid, therefore, we proceeded with the sale.
A. The contract was valid; therefore, we proceeded with the sale.
Semicolon before 'therefore' joining two independent clauses.
Transcript Notes
These words are by nature adverbs but become conjunctions when moved to the front of an independent clause. To be considered a conjunctive adverb, the word must be the first word of an independent clause. If the word is in the middle of the sentence, it is not a conjunction — it is simply an adverb or parenthetical, and the semicolon punctuation does not apply.
Common conjunctive adverbs include: however, therefore, consequently, furthermore, moreover, nevertheless, otherwise, in fact, in addition, hence, indeed, likewise, plus, so (meaning 'therefore'), still, then, thus, yet. A conjunctive adverb can never begin a conversation — 'Therefore, we want it back' requires a prior thought to link back to.
It is not a good idea to string several semicolons with conjunctive adverbs in succession — use a period in places to break it up.
Style Guide References (3)
Morson's
BGGP
BGGP