8. LIÊN TỪ

8.1. Định nghĩa: Liên từ là những từ dùng để nối các từ, cụm từ, mệnh đề hoặc câu.

VD: We eat at home and work in the office. (Liên từ "and" được dùng để nối câu: "we eat at home" với "we work in the office").

8.2. Các loại liên từ:

a. Liên từ liên kết: dùng để nối các từ, nhóm từ có chức năng giống nhau (danh từ với danh từ, động từ với động từ, tính từ với tính từ ...) hoặc các mệnh đề độc lập về mặt ngữ pháp. Loại liên từ này được chia làm bốn nhóm:

LIÊN TỪ PHẦN ĐƯỢC NỐI VÍ DỤ
and cụm danh từ + cụm danh từ We have tickets for the symphony and the opera.
but câu + câu The orchestra rehearses on Tuesday, but the chorus rehearses on Wednesday.
or động từ + động từ Have you seen or heard the opera by Scott Joplin?
so câu + câu I wanted to sit in the front of the balcony, so I ordered my tickets early.

- Nhóm AND: chỉ sự thêm vào, bao gồm các liên từ: and, as well as và các trạng từ: besides, furthermore, moreover và cụm từ in addition được dùng để nối hai mệnh đề hoặc hai câu độc lập.

VD: Mrs. Pike has a yacht and a helicopter. In addition, she has five cars.

He is a talented musician as well as being a professional photographer.

- Nhóm BUT: chỉ sự mâu thuẫn hoặc trái ngược, bao gồm các liên từ: but, yet, still; các trạng từ: however, nevertheless, và cụm từ on the other hand được dùng để nối hai mệnh đề hoặc câu độc lập.

VD: My son is intelligent but lazy.

We thought that Tom should accept the offer. Nevertheless, he turned it down.

- Nhóm OR: chỉ sự lựa chọn hoặc đoán chừng, bao gồm các liên từ: or, or else, otherwise

VD: Hurry up or else you'll be late.

- Nhóm SO: chỉ hậu quả, kết quả, bao gồm các liên từ: so, therefore, for; trạng từ consequently, và cụm từ as a result

VD: There weren't enough beds, so we had to sleep on the floor.

b. Liên từ quan hệ: Liên từ này luôn đi theo cặp, cũng được dùng để nối các từ, nhóm từ có chức năng giống nhau (danh từ với danh từ, động từ với động từ, tính từ với tính từ ...) hoặc các mệnh đề độc lập về mặt ngữ pháp.

LIÊN TỪ PHẦN ĐƯỢC NỐI VÍ DỤ
both...and chủ ngữ + chủ ngữ Both my sister and my brother play the piano.
either...or danh từ + danh từ Tonight's program is either Mozart or Beethoven.
neither...nor chủ ngữ + chủ ngữ Neither the orchestra nor the chorus was able to overcome the terrible acoustics in the church.
not only...but also câu + câu Not only does Sue raise money for the symphony, but she also ushers at all of their concerts.

Dưới đây là một số cặp liên từ quan hệ thường gặp:

both ... and He is both intelligent and good-natured.
either ... or I will either go for a walk or read a book.
neither ... nor He is neither rich nor famous.
hardly ... when He had hardly begun to work, when he was interrupted.
if ... then If that is true, then what happened is not surprising.
no sooner ... than No sooner had I reached the corner, than the bus came.
not only ... but also She is not only clever, but also hard-working.
rather ... than I would rather go swimming than go to the library.
scarcely ... when Scarcely had we left home, when it started to rain.
what with ... and What with all her aunts, uncles and cousins, she has many relatives.
whether ... or Have you decided whether you will come or not?

c. Liên từ phụ thuộc: dùng để mở đầu một mệnh đề phụ (mệnh đề danh từ hoặc mệnh đề trạng từ).

Dưới đây là một số ví dụ về liên từ phụ thuộc:

LIÊN TỪ VÍ DỤ
after We are going out to eat after we finish taking the test.
since Since we have lived in Atlanta, we have gone to every exhibit at the High Musuem.
while While I was waiting in line for the Matisse Exhibit, I ate my lunch.
although Although the line was long and the wait over two hours, the exhibit was well worth it.
even if Even if you have already bought your ticket, you will still need to wait in line.
because I love Matisse's works because he uses color so brilliantly.

Liên từ phụ thuộc bao gồm các nhóm sau:

THỜI GIAN NGUYÊN NHÂN VÀ KẾT QUẢ HOẶC MỤC ĐÍCH TƯƠNG PHẢN ĐIỀU KIỆN
after because although if / as long as
before since though unless
when now that even though

only if
while as whereas whether or not
since in order that while even if
until so / so that even if in case (that)
as soon as seeing that provided that
by the time in order that supposing that

Một số ví dụ về liên từ phụ thuộc:

As he is my friend, I will help him.

After the train left, we went home.

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

All will be well, providing you are careful.

Supposing that happens, what will you do?

As long as we cooperate, we can finish the work easily.

I am going out even if it rains.

Bài tập luyện

Exercise 13. Choose the best completion

1. I couldn't sleep ___ very tired.

A. although I was

B. despite I was

C. despite of being

D. in spite of to be

2. You probably won't need it, but I'll give you my phone number ___ to contact me.

A. in case you will need

B. if you will need

C. if you need

D. in case you need

3. I have to eat breakfast in the morning. ___, I get grouchy and hungry before my lunch break.

A. Consequently

B. And

C. Otherwise

D. However

4. My mouth is burning! This is ___ spicy food that I don't think I can finish it.

A. such

B. so

C. very

D. too

5. I need to find an apartment before I can move. ___ I can find one in the next week or so, I will move to Chicago the first of next month.

A. If

B. Even if

C. Whether

D. Only if

6. ___ want to take a train trip across western Canada, but my traveling companion wants to fly to Mexico City for our vacation.

A. Although I

B. Even if I

C. I

D. Despite I

7. Peter works hard at everything he does. His brother, ___ , seldom puts out much effort.

A. on the other hand

B. otherwise

C. even though

D. consequently

8. A newborn baby can neither walk nor crawl. A newborn antelope, ___ , can run within minutes of birth.

A. however

B. nevertheless

C. otherwise

D. even though

Choose one phrase or clause that best completes each of the following sentences.

9. ___ , only seven of her poems were published while she was alive.

A. Whereas Emily Dickinson was now a well-known American poet

B. In spite Emily Dickinson a well-known American poet

C. But for Emily Dickinson now a well-known American poet

D. Despite the fact that Emily Dickinson is now a well-known American poet

10. ___ , it is one of the most important climatic factors in the formation of desert erosion features.

A. Although rainfall in the desert is low

B. While rainfall in the desert is low

C. Despite the desert having low rainfall

D. Due to rainfall in the desert being low

11. On Saturday evening, I either go to the cinema ___ .

A. or stay at home and watch TV

B. nor stay at home and watch TV

C. or staying at home and watching TV

D. or staying at home and watching TV

Choose one option A, B, C or D that best combines the two sentences.

12. The man opened the window. He wanted to get some fresh air in the room.

A. The man opened the window so he wanted to get some fresh air in the room.

B. The man opened the window in order to get some fresh air in the room.

C. The man opened the window in order for getting some fresh air in the room.

D. The man opened the window therefore he could get some fresh air in the room.

13. Richard is not in class today. Mary is not in class today.

A. Neither Richard nor Mary is in class today.

B. Either Richard or Mary is in class today.

C. Both Richard and Mary are in class today.

D. Richard is not in class today but Mary is.

14. Tommy is practicing the piano day and night. He wants to play for the dance.

A. In order to be able to play for the dance Tommy is practicing the piano day and night.

B. Tommy is practicing the piano day and night in order that he wants to play for the dance.

C. Tommy is practicing the piano day and night so that he can play for the dance.

D. Both A & C are correct.