Learn on PengiElements of Language, 5th CourseChapter 13: Punctuation: End Marks and Commas

Lesson 1: End Marks and Abbreviations

In this Grade 8 grammar lesson from Elements of Language, 5th Course, students learn how to use the four types of end marks — periods, question marks, and exclamation points — with declarative, interrogative, exclamatory, and imperative sentences. The lesson also covers the correct use of periods with abbreviations, including personal names, social titles such as Dr. and Mrs., and civil or military titles. Practice exercises help students identify sentence types and apply the appropriate punctuation in context.

Section 1

Declarative and Interrogative Sentences

Definition

A statement (or declarative sentence) is followed by a period. A question (or interrogative sentence) is followed by a question mark.

Explanation

Sometimes a sentence is phrased as a statement but is actually asking a question indirectly. It's important to look at the sentence's purpose. If it's making a statement, even if it's about a question someone asked, it ends with a period. If it directly asks something, it needs a question mark.

Examples

  • I watched an interesting documentary about volcanoes. [This sentence is a declarative sentence because it makes a statement and should end with a period.]
  • Did Michael see the movie as well? [This sentence is an interrogative sentence because it asks a question and should end with a question mark.]
  • He asked if I had finished my science project. [This sentence is a statement reporting a question, so it is declarative and needs a period.]

Section 2

Exclamatory and Imperative Sentences

Definition

An exclamation (or exclamatory sentence) is followed by an exclamation point. A request or command (or imperative sentence) is generally followed by either a period or an exclamation point.

Explanation

An exclamatory sentence shows strong feeling and always gets an exclamation point. An imperative sentence gives a command or makes a request. Use a period for a gentle request or a mild command. Save the exclamation point for strong, urgent commands to show excitement or danger!

Examples

  • Wow! That was an amazing goal! [This is an exclamatory sentence because it shows strong emotion and needs an exclamation point.]
  • Please feed the cat before you leave. [This imperative sentence is a request and should end with a period.]
  • Look out for that falling rock! [This imperative sentence is a strong command and requires an exclamation point.]

Section 3

Abbreviations: Personal Names and Titles

Definition

Use a period after certain abbreviations.

Explanation

Use a period for abbreviations in people's names, like initials. Social titles (like Mr. or Dr.) and civil/military titles (like Sen. or Col.) are abbreviated before a full name. However, you should spell out civil and military titles when they are used with only a last name. Also, if a professional degree like M.D. follows a name, don't use a social title like Dr. at the beginning.

Examples

  • The lecture was given by Prof. Winston S. Grant of Oxford University. [An initial and an abbreviated title both need a period.]
  • Maria Rodriguez, Ph.D., is an expert on marine ecosystems. [An academic degree following a name is abbreviated with periods.]
  • The ceremony was led by Gen. Robert Abrams. [A military title before a full name is abbreviated.]
  • We need to speak with Captain Miller. [A military title before a last name only is spelled out.]

Section 4

Agencies, Organizations, and Acronyms

Definition

An acronym is a word formed from the first letters of a group of words.

Explanation

An acronym is a shortcut made from the first letter of each word in a name, like NASA for National Aeronautics and Space Administration. A key rule to remember is that acronyms are written without periods. When you first mention an organization in your writing, it's best to spell out the full name, and then you can use the acronym afterward.

Examples

  • The correct acronym for the Federal Bureau of Investigation is FBI. [Acronyms are formed from the first letters and do not use periods.]
  • The correct acronym for the National Football League is NFL. [Common organizations are known by their acronyms, written without periods.]
  • The correct acronym for the Parent-Teacher Association is PTA. [Acronyms are written without periods.]

Section 5

Abbreviations: Geographical Terms

Definition

Use a period after certain abbreviations.

Explanation

When writing a story or essay (what we call regular text), you should spell out the names of states and words in an address, like 'Street' or 'Avenue.' However, it's okay to abbreviate these terms in tables, footnotes, or on an envelope. Remember, the special two-letter state abbreviations like CA or TX are only used when a ZIP Code is included.

Examples

  • My cousin lives and works in Portland, Oregon. [In regular text, state names are spelled out.]
  • Mail the package to 1450 Oak St., Denver, CO 80204. [On an envelope with a ZIP code, use the two-letter state abbreviation without a period.]
  • In a table, 'Los Angeles, California' can be written as Los Angeles, Calif. [In tables and notes, traditional abbreviations with periods are used.]

Section 6

Abbreviations: Units of Measurement

Definition

Use a period after certain abbreviations.

Explanation

In your everyday writing, always spell out units of measurement like 'pounds' or 'feet.' You should only use abbreviations for these units in special cases like tables or scientific notes. One tricky rule: most measurement abbreviations don't use a period, but the abbreviation for 'inch' (in.) does! This is to avoid confusing it with the word 'in'.

Examples

  • The recipe requires two cups of flour. [In regular text, units of measurement are spelled out.]
  • The board must be 7 ft long. [In notes or tables, abbreviations are used. 'ft' for feet does not need a period.]
  • The phone screen is 6 in. wide. [The abbreviation for 'inch' always uses a period to avoid confusion with the word 'in'.]

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Chapter 13: Punctuation: End Marks and Commas

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    Lesson 2: Commas with Items in a Series, Independent Clauses, and Nonessential Clauses and Phrases

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Section 1

Declarative and Interrogative Sentences

Definition

A statement (or declarative sentence) is followed by a period. A question (or interrogative sentence) is followed by a question mark.

Explanation

Sometimes a sentence is phrased as a statement but is actually asking a question indirectly. It's important to look at the sentence's purpose. If it's making a statement, even if it's about a question someone asked, it ends with a period. If it directly asks something, it needs a question mark.

Examples

  • I watched an interesting documentary about volcanoes. [This sentence is a declarative sentence because it makes a statement and should end with a period.]
  • Did Michael see the movie as well? [This sentence is an interrogative sentence because it asks a question and should end with a question mark.]
  • He asked if I had finished my science project. [This sentence is a statement reporting a question, so it is declarative and needs a period.]

Section 2

Exclamatory and Imperative Sentences

Definition

An exclamation (or exclamatory sentence) is followed by an exclamation point. A request or command (or imperative sentence) is generally followed by either a period or an exclamation point.

Explanation

An exclamatory sentence shows strong feeling and always gets an exclamation point. An imperative sentence gives a command or makes a request. Use a period for a gentle request or a mild command. Save the exclamation point for strong, urgent commands to show excitement or danger!

Examples

  • Wow! That was an amazing goal! [This is an exclamatory sentence because it shows strong emotion and needs an exclamation point.]
  • Please feed the cat before you leave. [This imperative sentence is a request and should end with a period.]
  • Look out for that falling rock! [This imperative sentence is a strong command and requires an exclamation point.]

Section 3

Abbreviations: Personal Names and Titles

Definition

Use a period after certain abbreviations.

Explanation

Use a period for abbreviations in people's names, like initials. Social titles (like Mr. or Dr.) and civil/military titles (like Sen. or Col.) are abbreviated before a full name. However, you should spell out civil and military titles when they are used with only a last name. Also, if a professional degree like M.D. follows a name, don't use a social title like Dr. at the beginning.

Examples

  • The lecture was given by Prof. Winston S. Grant of Oxford University. [An initial and an abbreviated title both need a period.]
  • Maria Rodriguez, Ph.D., is an expert on marine ecosystems. [An academic degree following a name is abbreviated with periods.]
  • The ceremony was led by Gen. Robert Abrams. [A military title before a full name is abbreviated.]
  • We need to speak with Captain Miller. [A military title before a last name only is spelled out.]

Section 4

Agencies, Organizations, and Acronyms

Definition

An acronym is a word formed from the first letters of a group of words.

Explanation

An acronym is a shortcut made from the first letter of each word in a name, like NASA for National Aeronautics and Space Administration. A key rule to remember is that acronyms are written without periods. When you first mention an organization in your writing, it's best to spell out the full name, and then you can use the acronym afterward.

Examples

  • The correct acronym for the Federal Bureau of Investigation is FBI. [Acronyms are formed from the first letters and do not use periods.]
  • The correct acronym for the National Football League is NFL. [Common organizations are known by their acronyms, written without periods.]
  • The correct acronym for the Parent-Teacher Association is PTA. [Acronyms are written without periods.]

Section 5

Abbreviations: Geographical Terms

Definition

Use a period after certain abbreviations.

Explanation

When writing a story or essay (what we call regular text), you should spell out the names of states and words in an address, like 'Street' or 'Avenue.' However, it's okay to abbreviate these terms in tables, footnotes, or on an envelope. Remember, the special two-letter state abbreviations like CA or TX are only used when a ZIP Code is included.

Examples

  • My cousin lives and works in Portland, Oregon. [In regular text, state names are spelled out.]
  • Mail the package to 1450 Oak St., Denver, CO 80204. [On an envelope with a ZIP code, use the two-letter state abbreviation without a period.]
  • In a table, 'Los Angeles, California' can be written as Los Angeles, Calif. [In tables and notes, traditional abbreviations with periods are used.]

Section 6

Abbreviations: Units of Measurement

Definition

Use a period after certain abbreviations.

Explanation

In your everyday writing, always spell out units of measurement like 'pounds' or 'feet.' You should only use abbreviations for these units in special cases like tables or scientific notes. One tricky rule: most measurement abbreviations don't use a period, but the abbreviation for 'inch' (in.) does! This is to avoid confusing it with the word 'in'.

Examples

  • The recipe requires two cups of flour. [In regular text, units of measurement are spelled out.]
  • The board must be 7 ft long. [In notes or tables, abbreviations are used. 'ft' for feet does not need a period.]
  • The phone screen is 6 in. wide. [The abbreviation for 'inch' always uses a period to avoid confusion with the word 'in'.]

Book overview

Jump across lessons in the current chapter without opening the full course modal.

Continue this chapter

Chapter 13: Punctuation: End Marks and Commas

  1. Lesson 1Current

    Lesson 1: End Marks and Abbreviations

    LearnPractice
  2. Lesson 2

    Lesson 2: Commas with Items in a Series, Independent Clauses, and Nonessential Clauses and Phrases

    LearnPractice
  3. Lesson 3

    Lesson 3: Commas with Introductory Elements, Interrupters, and in Conventional Situations

    LearnPractice