Conjunctions & Linking Words: and / but / because / so

A2 Grammar

1. Simple explanation

A conjunction is a joining word — it connects words or clauses (a clause is a part of a sentence with its own subject and verb). And adds more, but shows the opposite, or offers a choice, because gives the reason (it answers 'Why?'), and so gives the result (what happened next). First, then, and finally show the order of steps.

2. Detailed explanation

Start from zero. A sentence is a complete idea with a verb: 'I was tired.' A verb is a word that shows an action or a state. A clause is a part of a sentence that has its own subject and verb — 'I was tired' is one clause, and 'I went to bed' is another clause. Short separate sentences can sound like robot talk: 'I was tired. I went to bed. I slept well.' A conjunction is a joining word. It connects words, parts, or whole clauses into one smooth sentence: 'I was tired, so I went to bed.' This lesson teaches five joining words: and, but, or, because, and so.

And, but, and or are the three basic joiners. And adds information in the same direction: 'I bought apples and oranges.' But shows a contrast — the second part is a surprise or the opposite of what you expect: 'The soup was cheap, but it was delicious.' Or gives a choice between two things; you pick one: 'Do you want tea or coffee?' Take one apart word by word: 'She called her friend, and they talked for an hour' — She (the person) + called (the action) + her friend (who she called) + and (the joiner: more is coming) + they talked (a second clause with its own verb) + for an hour (how long). When and joins two clauses, careful writers put a comma before it.

Because and so connect a reason and a result, but they look in opposite directions. Because answers 'Why?': 'I stayed home because I was sick.' The because-part gives the reason, so it must be a full clause with a subject and a verb — never just a noun. The idea also works in the other order: 'Because I was sick, I stayed home.' When the because-part comes first, put a comma after it. So gives the result — what happened after the reason: 'I was sick, so I stayed home.' Most important warning: never use because and so in the same sentence. English chooses one joiner, not both: ✗ 'Because I was sick, so I stayed home.' Pick one, and the sentence is perfect.

First, then, next, and finally are linking words for order: 'First, mix the flour. Then, add the eggs. Finally, bake the cake.' They do not join clauses like and or but — each step is its own sentence. One more pattern: both … and … joins two things and means 'the two together': 'Both the soup and the salad were fresh.' The verb is plural — were, not was — because the two things count together.

3. Formula / structure

Step by step — how to build a sentence:

and / but / or:

because:

both … and …:

sequence words:

so:

4. When to use it

• Joining two actions or facts: 'She cooked dinner and washed the dishes.'
• Adding words in a list: 'We need milk, eggs, and bread.'
• Showing a contrast or surprise: 'He is rich, but he isn't happy.'
• Offering a choice: 'Would you like soup or salad?'
• Giving a reason — answering 'Why?': 'I called because I needed help.'
• Showing a result: 'The road was closed, so we were late.'
• Telling the order of steps in a story, recipe, or instructions: 'First… Then… Finally…'

5. When NOT to use it

• Don't use because and so in the same sentence: ✗ 'Because it rained, so we stayed in.' Pick one joiner.
• Don't use so to give a reason: ✗ 'I left so I was tired' → ✓ 'I left because I was tired.'
• Don't join two full sentences with only a comma and no joining word in careful writing: ✗ 'I was tired, I went to bed' → ✓ 'I was tired, so I went to bed.'
• Don't use and when you offer a choice of one: at a cafe, 'Coffee or tea?' — not 'Coffee and tea?' (unless you really mean both).
• Don't start every sentence with And or But in formal writing. In speech it is natural, but in an essay, join the ideas inside the sentence instead.

6. Positive examples

• I bought apples and oranges at the market.
• She speaks English and a little Spanish.
• The hotel was cheap, but it was very clean.
• He studied hard, but he failed the test.
• Do you want tea or coffee?
• We can walk, or we can take the bus.
• I stayed home because I was sick.
• She is happy because her team won the game.
• It was raining, so we took a taxi.
• He was hungry, so he made a sandwich.
• First, wash the rice. Then, add the water. Finally, cook it for twenty minutes.
• Both the soup and the salad were delicious.

7. Negative examples

• I'm not hungry, so I'm not eating lunch today.
• She didn't call because she lost her phone number.
• We can't go to the beach because the weather is bad.
• He doesn't eat meat, but he eats fish.
• The store isn't open, so we can't buy bread.
• I don't want tea or coffee, thank you.

8. Questions

• Do you want juice or water?
• Why are you late today?
• Did she cry because she was sad?
• Is he coming with us, or is he staying home?
• What do we do first?
• Would you like the chicken or the fish?

9. Short answers

• Because I was tired. (answering 'Why…?')
• Coffee, please. (choosing after '…or…?')
• Both, please.
• Me too. (agreeing with an 'and' sentence)
• So did I. (agreeing about a past action)
• Then we went home.

10. Common mistakes

11. American English notes

12. Similar grammar — comparison

13. Natural spoken English

• 'I'm tired, so I'm gonna head home.'
• 'Why are we stopping?' — 'Because I said so!'
• 'Coffee or tea?' — 'Coffee, please. Black.'
• 'It was raining, but we went to the game anyway.'
• 'First he called me, then he sent a text.'
• 'So… what happened next?'

14. Real-life examples

• A recipe: 'First, heat the oil. Then, add the onions and cook for five minutes.'
• Explaining at work: 'I'm late because the train was delayed.'
• A text message: 'Stuck in traffic, so I'll be ten minutes late.'
• On a sign: 'No food or drinks in the library.'
• Giving directions: 'Turn left at the bank, and then walk two blocks.'
• An email: 'The meeting is moved to Friday because the manager is traveling.'

15. Mini dialogue

16. Summary

17. Practice exercises

Warm up with the first questions, then take the full quiz — every answer has a detailed explanation (parts 19–20 of this lesson: answer key + explanations live inside the quiz feedback).

18. The full quiz

50 questions, mixed formats, in difficulty order: easy → medium → intermediate → challenging → advanced.

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