conjunctive adverbs and semicolons

When a conjunctive adverb joins two independent clauses, use a semicolon before it and a comma after it: The train was late; however, we waited. A period is also correct: The train was late. However, we waited. Do not join the clauses with a comma alone. The common conjunctive adverbs are however, therefore, moreover, furthermore, nevertheless, nonetheless, consequently, accordingly, otherwise, instead, meanwhile, and besides.