Conventions of Composition Rule 5

Rule: Use a comma or commas to separate long or inessential phrases from the essential elements of the sentence.

Examples:

Wrong: In the beginning of the chapter on microbiology the publishers printed six photos of cells.

Better: In the beginning of the chapter on microbiology, the publishers printed six photos of cells.

Wrong: At his house in Vermont behind a lake and dark woods he taps every tree.

Better: At his house in Vermont behind a lake and dark woods, he taps every tree.

Wrong: The Star-Spangled Banner sung loudly at every baseball game is my favorite anthem.

Better: The Star-Spangled Banner, sung loudly at every baseball game, is my favorite anthem.

Practice deciding if and where these sentences need commas:

1. On the hill by the tennis courts beyond the MAC you can find the Vietnam Memorial.

2. In 1972 The Godfather came out.

3. After the longest 108 years ever the Cubs finally won the World Series.

4. Of all of the students taking Shakespeare and the Bible only seven memorized all of Hamlet.

Resources for further explanation of how to punctuate inessential phrases:

Purdue OWL's Commas

English Plus's Commas After Introductory Phrase