Transcript Document

Punctuation I
Punctuation

Punctuation in English writing is like traffic
lights and traffic signs. It helps the reader
understand what you are writing. The
punctuation marks used most commonly
in English are:
 Comma
(,)
 Semicolon (;)
 Colon (:)
 Apostrophe (’)
 Period (.)
 Question Mark (?)
 Exclamation point (!)
 Quotation mark (“)
The Comma

Use a comma before a coordinating
conjunction (and, but, or, nor, for, so, yet)
when it is used to join independent clauses.


She looks very young, but she is already in her
30's.
If the two independent clauses are short and
not likely to be misread, no comma is
needed.

The plane took off and we were on our way.

Use a comma after an introductory clause
or phrase.

When Sam looked in the path near the school
building, he found his lost book.

When Mary was ready to eat, her cat jumped
onto the table.

Use a comma after an introductory
participial phrase that describes the noun
or pronoun that follows.

Struggling with large amounts of homework,
the class feared the exam.

Having seen pictures of the beach, the
children eagerly looked forward to summer.
Exercise 1.1: add or delete commas

As the concert began we heard a tremendous explosion.

With their local knowledge and low population density the
people can fulfill their daily living needs by using the
natural resources around them.

Further the steep topography makes most of the land very
susceptible to erosion.

Beyond these flat riverside areas low nutrients shallow
soil poor drainage and high rainfall limit the development
of large plantations.

Use a comma between all items in a
series.

I brought my books, papers, and computer
to the classroom.

We will prepare the specimens, conduct the
tests, and record the data.

Use a comma between coordinate
adjectives not joined with and.

Same has become a strong, confident,
independent man.

The laboratory is a small, windowless, poorly
lighted room.

The laboratory is a windowless, poorly lighted,
small room.
(Coordinate adjectives can be scrambled.)

Do not use a comma between cumulative
adjectives.

Three large gray trucks tooled down the street.
(Cumulative adjectives do not modify a noun
separately.)
 Three
gray large trucks rolled down the street.
(Do not scramble cumulative adjectives.)
Exercise 1.2: add or delete commas

My brother and I found a dead snake picked it up and
placed it on the teacher’s doorstep.

For breakfast the children ordered rice doughnuts with
peanut butter and chocolate milk.

The region is not suited for large-scale agricultural
activities such as planting pepper coffee cocoa candlenut
and rubber or oil palm.

An ambulance threaded its way through police cars fire
trucks and irate citizens.

Use commas to set off nonrestrictive
elements

The truck, with its horn blowing loudly, rushed
through the streets of the city.

This research, which I began two years ago, is
beginning to show some interesting results.
(Removing a nonrestrictive element does not
greatly change the meaning of the sentence.)

Do not use commas to set of restrictive
elements.

A laboratory that is well ventilated is
needed for this type of research.

The corner of the laboratory was filled with
notebooks that dated from ten years ago.

The novel “The Naked and the Dead” was
Norman Mailer’s first novel.

Use commas to set off transitional
expressions.
However, therefore, moreover, for
example, as a matter of fact, in other
words

As a matter of fact, many of the musicians
have hearing problems

Therefore, they frequently need hearing
assistance.
If a transitional expression is between
independent clauses, precede it with a
semicolon (;) and follow it with a comma.

Natural foods are not always salt free; for
examples, celery contains more salt than most
people would imagine.

The new building is not completed; however,
this classroom is air-conditioned.

Use commas to set off parenthetical
expressions.

Evolution, as far as we know, doesn’t work
this way.

The fish weighed about five kilograms, give or
take a few grams.

Learning English, unfortunately for students,
is a complex and frustrating process.

Use commas to set off absolute phrases.

Elvis Presley made music history in the 1950s,
his records having sold more than ten
million copies.

The weather having become very bad, the
airplane was unable to take off.
(Of course, these two sentences could be
written in another way)

Use commas to set off contrasting
elements.
Sharp contrasts begin with words such as not,
never, and unlike.

Unlike Robert, Celia loved speech contests.

We use alcohol, never water, to sterilize the
instruments.

Use commas to set off direct address,
question tags, and interjections.

Forgive us, Professor, for being late in sending
our homework.

Yes, but don’t do it again.

This is the third time you have been late, isn’t
it?

Well, we sometimes have lots of other
homework to do.

Use commas to set off direct quotations.

William Shakespeare, in “Twelfth Night”,
said “God give them wisdom, that have it;
and those that are fools, let them use
their talents.”

“I know not what course other may take,
but, as for me, give me liberty or give me
death”, said Patrick Henry before the
American Revolution.

Use commas to set off dates, addresses,
titles, and numbers.

The final examination will be on June 22, 2007.

C. H. Wong, Ph.D., has been appointed to be
the President of Academia Sinica.

The teacher was born in Hualien, Taiwan, in
1960.

The total price is NTD 23,456.

Use commas to avoid confusion.

To err is human; to forgive, divine.

Of all the baseball games we played, this
was the worst.

All of the catastrophes that we feared might
happen, happened.
Exercise 1.3: add or delete commas


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We will do our work in the laboratory that is on the third
floor.
We will do our work in the chemistry laboratory which is
on the third floor.
The surprising thing however was the items that sold
most quickly.
Whenever the weather is rainy they wear raincoats and
boots which keep them dry.
Although, the air was warm, the water was too cold for
swimming.
Come to think of it more than forty years have passed
since then.
The Period

Use a period to end a sentence.
Bill asked whether our class will be
cancelled tomorrow.
 The period is a red light or stop sign.
 “The period is the most powerful piece of
punctuation at your disposal. In many
scientific documents periods are not used
often enough.”
Michael Alley The craft of Scientific

Writing

Use a period to improve the flow of writing. Sometimes,
there are too many ideas packed into one sentence.
Use periods and shorter sentences as follows to
improve the flow and understanding.
1. For temperatures above 1100K, the four fuels had about the same
ignition delay when the ignition delay was defined as the time to
recover the pressure loss from fuel evaporation, in spite of the large
variations in ignition delay among the four fuels at lower temperatures.
2. Ignition delay is the time required to recover the pressure loss from
fuel evaporation. Despite the large variations in ignition delay at lower
temperatures, the four fuels had about the same ignition delay for
temperatures above 1100K.

Use a period in conventional abbreviations.
Mr. (mister);
Mrs. (misses)
Dr. (doctor);
Ph.D. (Doctor of Philosophy)
e.g. (exempli gratia);
etc. (et cetera)
i.e. (id est);
p.s. (post scriptum)

Sometimes the period is omitted in an abbreviation using
capital letters:
AM
BA

PM
MA
Do not use a period in abbreviating names of organizations.
UN
IBM
USA
FAO
WHO
ILO
Bonne soiree
Bon soir
Taipei Basin