Liên từ (Conjunctions)

Liên từ và cách sử dụng
1. Liên từ kết hợp (coordinating conjunctions)

  • Dùng loại liên từ này để nối những các từ loại hoặc cụm từ/ nhóm từ cùng một loại, hoặc những mệnh đề ngang hàng nhau (tính từ với tính từ, danh từ với danh từ …)
  • Gồm có: for, and, nor, but, or, yet
  • Ví dụ:
She is a good and loyal wife.
Use your credit cards frequently and you’ll soon find yourself deep in debt.
He is intelligent but very lazy.
She says she does not love me, yet I still love her.
We have to work hard, or we will fail the exam.
He will surely succeed, for (because) he works hard.
That is not what I meant to say, nor should you interpret my statement as an admission of guilt.

• Chú ý: khi dùng liên từ kết hợp để nối hai mệnh đề, chúng ta thêm dấu phẩy sau mệnh đề thứ nhất trước liên từ

Ulysses wants to play for UConn, but he has had trouble meeting the academic requirements.

2. Tương liên từ (correlative conjunctions)

  • Một vài liên từ thường kết hợp với các từ khác để tạo thành các tương liên từ. Chúng thường được sử dụng theo cặp để liên kết các cụm từ hoặc mệnh đề có chức năng tương đương nhau về mặt ngữ pháp
  • Gồm có: both . . . and…(vừa….vừa…), not only . . . but also… (không chỉ…mà còn…), not . . . but, either . . . or (hoặc ..hoặc..), neither . . . nor (không….cũng không…), whether . . . or , as . . . as, no sooner…. than…(vừa mới….thì…)
  • Ví dụ:
They learn both English and French.
He drinks neither wine nor beer.
I like playing not only tennis but also football.
I don’t have either books or notebooks.
I can’t make up my mind whether to buy some new summer clothes now or wait until the prices go down.

3. Liên từ phụ thuộc (subordinating conjunctions)

  • Loại liên từ phụ thuộc nối kết các nhóm từ, cụm từ hoặc mệnh đề có chức năng khác nhau – mệnh đề phụ với mệnh đề chính trong câu.
  • Ví dụ như các liên từ sau và nghĩa kèm theo của chúng:

1. Bởi vì: As he is my friend, I will help him.
2. Khi: We watched as the plane took off.

After: sau khi

After the train left, we went home.

Although/ though: mặc dù

Although it was after midnight, we did not feel tired.

Before: trước khi

I arrived before the stores were open.

Because: bởi vì

We had to wait, because we arrived early.

For: bởi vì

He is happy, for he enjoys his work.

If: nếu, giá như

If she is here, we will see her.

Lest: sợ rằng

I watched closely, lest he make a mistake.

Chú ý: sử dụng động từ nguyên thể trong mệnh đề “lest”
Providing/ provided: miễn là

All will be well, providing you are careful.


1. Từ khi: I have been here since the sun rose.
2. Bởi vì: Since you are here, you can help me.

So/ so that

1. Bởi vậy: It was raining, so we did not go out.
2. Để (= in order that): I am saving money so I can buy a bicycle.

Supposing (= if)

Supposing that happens, what will you do?

Than: so với

He is taller than you are.

Unless: trừ khi

Unless he helps us, we cannot succeed.

Until/ till: cho đến khi

I will wait until I hear from you.


1. Bởi vì: Whereas this is a public building, it is open to everyone.
2. Trong khi (ngược lại): He is short, whereas you are tall.

Whether: hay không

I do not know whether she was invited.


1. Khi: While it was snowing, we played cards.
2. Trong khi (ngược lại): He is rich, while his friend is poor.
3. Mặc dù: While I am not an expert, I will do my best.

As if = in a similar way

She talks as if she knows everything.

As long as

1. Nếu: As long as we cooperate, we can finish the work easily.
2. Khi: He has lived there as long as I have known him.

As soon as: ngay khi

Write to me as soon as you can.

As though = in a similar way

It looks as though there will be a storm.

In case: Trong trường hợp…

Take a sweater in case it gets cold.

Or else = otherwise: nếu không thì

Please be careful, or else you may have an accident.

So as to = in order to: để

I hurried so as to be on time.

Chú ý: Ngoài liên từ, chúng ta có thể sử dụng các trạng từ liên kết như therefore, otherwise, nevertheless, thus, hence, furthermore, consequently…
Ví dụ:

We wanted to arrive on time; however, we were delayed by traffic.
I was nervous; therefore, I could not do my best.
We should consult them; otherwise, they may be upset.

4. Phân biệt cách sử dụng của một số liên từ và giới từ có cùng nghĩa.

Liên từGiới từ
because of

 – Sự khác biệt giữa chúng là: liên từ + một mệnh đề, trong khi đó giới từ + một danh từ hoặc ngữ danh từ

– Ví dụ:

They were upset because of the delay
They were upset because they were delayed.

Despite the rain, we enjoyed ourselves.
Although it rained, we enjoyed ourselves.

We stayed indoors during the storm.
We stayed indoors while the storm raged.

Bài 1:

Câu hỏi 1 : Điền vào chỗ trống bằng những liên từ thích hợp:1. I’ll come and see you…….I leave for Moscow.2. He will tell you……… get home.3. I can’t express my opinion………I know the fact.4. We started very early……..we should miss the train.5. He will stay here…… come.6. ………..he tried hard, he wasn’t successful.7. He worked late last night……..he might be free to go away tomorrow.8. The room is ….small…..we can’t all get in.9. …….you had left earlier, you would have caught the train.10. The road seems longer…….I thought.11. ………it rained hard, we played the match.12. ……… may go, he won’t forget you.
  • 1.

    1. before

  • 2.

    2. when

  • 3.

    3. unless

  • 4.

    4. for fear that

  • 5.

    5. until

  • 6.

    6. although

  • 7.

    7. so that

  • 8.

    8. so….that

  • 9.

    9. if

  • 10.

    10. than

  • 11.

    11. even though/although

  • 12.

    12. wherever

Câu hỏi 2 : Viết lại những câu sau đây dùng liên từ thích hợp1. We know him. We know his friends.2. The coat was soft. The coat was warm.3. It is stupid to do that. It is quite unnecessary.4. I wanted to go. He wanted to stay.5. Your arguments are strong. They don’t convince me.6. You can go there by bus. You can go there by train.7. I was feeling tired. I went to bed when I got home.
  • 1.

    We know him and his friends.

  • 2.

    The coat was both soft and warm.