Conventions of Composition Rule 11
Rules: An adverbial clause at the beginning of a sentence must be followed by a comma. An adverbial clause at the end of a sentence should be preceded by a comma only if the clause is inessential (presented merely as additional or incidental information).
Examples:
Wrong: When you start with an adverbial clause you need to follow it with a comma.
Better: When you start with an adverbial clause, you need to follow it with a comma.
Correct: Come to our house after you finish work today. (Don't leave work early.)
Correct: Make hay while the sun shines. (Don't make hay at night.)
Correct: I am sorry I cannot go with you now, although perhaps I could some other day.
Practice deciding if and where these sentences could take commas:
- If he trains his dog to joggle (jog and juggle simultaneously) he could make a lot of money.
- Craig would love to sing in the musical if he gets a starring role.
- Buying a new car can cause stress when money becomes tight.
- Because she understood fractals she aced the exam.
Resources for further explanation of how to punctuate sentences containing adverbial clauses:
Towson's Dependent Clauses
Your Dictionary's Adverb Clauses