✏️ WritingGrade 2Lesson 3
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Join Ideas Using Conjunctions

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Learning Objectives

  • 1Name the five common conjunctions: and, but, so, or, because
  • 2Join two short sentences into one using the right conjunction
  • 3Choose the conjunction that matches the relationship between two ideas
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Mini Lesson

When you write two short sentences that belong together, you can join them into one using a special joining word called a conjunction.

The Five Conjunctions

  • and — adds one idea to another: I like cats and I like dogs.
  • but — shows a difference or surprise: I like cats but I am allergic.
  • so — shows a result: It was cold, so I wore my coat.
  • or — shows a choice: Do you want juice or water?
  • because — gives a reason: I smiled because I was happy.

How to Join Two Sentences

  • Write the first sentence without the period.
  • Add a comma if needed, then the conjunction.
  • Add the second idea after it.
  • Example: I was tired. I went to bed. → I was tired, so I went to bed.

Choosing the Right Conjunction

  • Ask: are the ideas similar? → use and
  • Ask: are the ideas opposite or surprising? → use but
  • Ask: is the second idea a result? → use so
  • Ask: is it a choice? → use or
  • Ask: is the second idea a reason? → use because
Five conjunction words with their meaningsFive pill-shaped labels showing and, but, so, or, because — each with a short meaning underneath.Conjunction Wordsandadds ideas togetherbutshows a differencesoshows a resultorgives a choicebecausegives a reasonThese joining words are called conjunctions.
Five conjunction words — and, but, so, or, because — each with its meaning in a color-coded label.
Two sentences joined into oneTwo short sentences before joining, and the compound sentence after using the conjunction so.Before and AfterIt was raining. I stayed inside.Two short sentences↓join with so↓It was raining, so I stayed.One longer sentence — much better!
Two short sentences joined into one using the conjunction "so."
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Ask yourself: "What is the relationship between these two ideas? Which conjunction fits best?"

Vocabulary
Conjunction
A joining word that connects two ideas or sentences into one longer sentencee.g. and, but, so, or, because
And
Adds one idea to another — used when the ideas are similare.g. I like apples and I like pears.
But
Shows a difference or surprise between two idease.g. It was sunny, but cold.
So
Shows that the second idea is a result of the firste.g. I was tired, so I slept.
Or
Gives a choice between two optionse.g. Juice or water?
Because
Gives the reason why something happense.g. I smiled because I was happy.
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