Grammar: B1 - ✨ Grammar Essentials: 🧩 Parts of Speech & 🏗️ Sentence Structure - Lesson 9: Conjunctions of Reason & Result (because - review, as, since, so - review)

Grammar: Conjunctions of Reason & Result

B1 Lesson 18: Using 'because', 'as', 'since', 'so'

What you will learn: By the end of this lesson, you will be able to use the conjunctions 'because', 'as', 'since', and 'so' to correctly link reasons and results in your sentences.

Explaining 'Why' and 'What Happened Next'

Good communication is logical. We often need to explain the reason something happens and the result of that reason. Conjunctions are the words that build these logical bridges in our sentences.

Conjunctions for Reasons: because, as, since

These three words all introduce the reason for an action. 'Because' is the most common and can be used in almost any situation. 'As' and 'since' are slightly more formal and are often used when the reason is already known to the listener.

Punctuation Rule: When the reason clause (starting with 'because', 'as', or 'since') comes first in the sentence, you must use a comma. If it comes second, no comma is needed.

• We decided to go swimming because it was very hot.
• Because it was very hot, we decided to go swimming.
• Since she knows the city well, she is an excellent tour guide.

Conjunction for Results: so

The word 'so' does the opposite job: it introduces the result of a situation. When connecting two complete sentences, always put a comma before 'so'.

• It was very hot, so we decided to go swimming.

The Grammar Rule 📖

Reason vs. Result Structures

Structure	Example
Result because Reason	He passed the exam because he studied hard.
Because Reason, Result	Because he studied hard, he passed the exam.
Reason, so Result	He studied hard, so he passed the exam.

In Conversation

Nary: I'm not going to the beach at Koh Rong tomorrow.

Chea: Really? Why not?

Nary: I'm not going because I have to work. Since I have a big project to finish, I need to stay home.

Chea: Oh, that's too bad. The weather forecast is great, so I'm sure it will be a beautiful day.

Practice Your Grammar 🎯

Exercise: Choose the Best Conjunction

Choose the best conjunction (because, so, as) to complete the sentences.

1. He was hungry, ______ he ordered a big bowl of kuy teav.
   → so
2. He ordered a big bowl of kuy teav ______ he was hungry.
   → because
3. ______ it was getting late, we decided to take a PassApp back to our hotel.
   → As / Since
4. I want to visit the Landmine Museum ______ I'm interested in Cambodian history.
   → because

Your Grammar Mission ⭐

Connect the Ideas

You are given a reason and a result. Your mission is to connect them into one logical sentence using 'so', and then write a second sentence using 'because'.

Reason: The weather was beautiful.
Result: We took a lot of photos at the temple.

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Sentence with 'so':
________________________________________________

Sentence with 'because':
________________________________________________

Key Vocabulary

• Reason (Noun) | ហេតុផល
  The cause or explanation for an action; it answers the question "Why?".
• Result (Noun) | លទ្ធផល
  A consequence or outcome of an action or event.