Cach dung dau phay trong tieng anh

The English House of Commas
This set of slides will illustrate the most common uses of one of the most common punctuation marks:
THE COMMA
Use the information icon and hyperlinks (this color) to link to sources of further information in the Guide to Grammar and Writing.
Use a comma to set off the elements of a series (three or more things), including the last two.
My favorite uses of the Internet are sending e-mail, surfing the Web, and using chat rooms.
You may have learned that this comma is not necessary.
Sometimes, however, the last two items in your series will glom into one if you don’t use the so-called serial comma.
The English House of Commas
Use a comma and a coordinating conjunction (and, but, or, nor, for, yet, so) to separate two independent clauses.
The public seems eager for some kind of gun control legislation, but the congress is obviously too timid to enact any truly effective measures.
If the two independent clauses are brief and nicely balanced, this comma may be omitted, but the comma is always correct.
Our team is very good but their team is better.
The English House of Commas
Use a comma to set off introductory elements.
Anxious about the upcoming winter, settlers began to bicker among themselves about supplies.
If the introductory element is brief and the sentence can be read easily without the comma, it can be omitted.
In 1649 the settlers abandoned their initial outpost.
The English House of Commas
In the winter of 1644, nearly half the settlers died of starvation or exposure.
Use a comma to separate coordinate adjectives.
Coaches grew weary of running practices in the drafty, dreary, dilapidated gymnasium.
If you could put a but or an and between the adjectives, you should put a comma between them.
expensive and modern = expensive, modern . . . . But not “a little and old house.” “A little old house” would be correct.
The English House of Commas
The designs for an expensive, modern gym should make them happy.
Use a comma to set off elements that express a contrast or a turn in the sentence.
The house was cute, but too expensive for the newlyweds.
The English House of Commas
They were looking for something practical, not luxurious
Use a comma to set off states and countries, years (in a full date), titles, etc.
The conference was originally set for Geneva, Switzerland, but was then rescheduled for Chicago, Illinois.
The English House of Commas
Their wedding date was set for August 5, 2000, in the college chapel in Newton, Massachusetts.
Tashonda Klondike, Chair of the Ways and Means Committee, submitted the committee’s final report.
Use a comma to set off quoted language.
Frost’s poem “Fire and Ice” begins with the lines, “Some say the world will end in fire, / Some say in ice.”
The English House of Commas
“Fire when ready, Gridley,” the Admiral said.
“We can’t see into the future,” said the President, “but we have to prepare for it nonetheless.”
Use a comma to set off parenthetical elements. This is the most difficult rule in comma usage. A parenthetical element is “added information,” something that can be removed from a sentence without changing the essential meaning of that sentence. Deciding what is “added information” and what is essential is sometimes difficult. See the next slide.
The English House of Commas
Parenthetical elements:
Robert Frost, perhaps America’s most beloved poet, died when he was 88.
The English House of Commas
Frankly, it doesn’t seem to matter.
When an appositive phrase can be removed from a sentence without changing its meaning or making it ambiguous:
An absolute phrase is treated as a parenthetical element:
An addressed person’s (or people’s) name is always parenthetical:
I am warning you, good citizens of Hartford, this vote is crucial to the future of our city.
One more parenthetical element:
Excuse me, but there are, of course, many points of view that we must consider before voting.
The English House of Commas
An interjection is treated as a parenthetical element:
One last rule: Don’t over-use commas! When a comma is needed, use it; otherwise, do without.
Reviewing the rules of comma usage will help you understand the way sentences are built — and that, ultimately, will help you become a better writer.
The English House of Commas
This PowerPoint presentation was created by
Charles Darling, PhD
Professor of English and Webmaster
Capital Community College
Hartford, Connecticut
copyright November 1999