The usage of transitional expressions, such as therefore, however, and in addition, helps your readers understand how you have organized your material, making it easier for them to go from one point to the next in your writing. You can use transitional expressions to: add ideas, emphasize ideas, illustrate ideas, compare ideas, show cause and effect, and summarize ideas. Commonly used transitional expressions are listed as follows:
◎ 添加/補充
Besides,
In addition ( In addition to…),
Moreover,
Furthermore,
Likewise,
Also,
Plus,
Again,
In terms of …,
When it comes to…,
As far as sth is concerned,
The same is (especially) true of…,
Meanwhile,
In the mean time,

◎ 對比/相反
But
Instead,
Instead of…,
Despite (prep.)…,
In spite of…,
However,
Nevertheless,
On the other hand,
On the contrary,
In contrast,
Rather,
….(,)While…..

◎ 因果(cause and effect)
因 + cause/ result in / lead to / contribute to / be responsible for + 果
果 + result from / be a result of / be a consequence of / be due to + 因
因 , leading to ( causing / leaving/resulting in) + 果
Because of…,
Due to…,
Thanks to…,
As a result of…,
Therefore,
Consequently, 
As a result,     
It follows that….
The reason why…. is that (because) ….
The reason for this is that…

◎ 讓步
Although
Perhaps
After all
Naturally
Though
….., though.

◎ 比較/類似
In a like manner (同樣的情形)
In the same way,
Similarly,
Likewise,
A is similar to B in that –
A is different from B in that…
A differs from B in that…
A is exactly (almost, quite) the same as B in that…
A resemble B in that…
…, and so am (did/do) I.

◎ 斷定(assertion)
There is no denying that…
There is no doubt that…
Of course,
In fact,
Certainly,
Doubtlessly,
Undoubtedly,
Naturally,
There was no exception that…
It is generally agreed that…
It is widely(generally) believed /acknowledged that…
This is particularly true of…
For better or worse,
For whatever reasons,

◎ 贊同
I agree with those who say that….
I agree that global warming is a serious problem.
I couldn’t agree more with the statement that…
I support the idea that…
I share the view that peace can only be achieved through dialogue.
I have always subscribed to the view that children should be given responsibility from an early age.(Formal)
I will support my view with the following reasons and examples.
In this discussion, I will try to establish the truth of the statement with reasons and examples drawn from my own experience.
In this essay, I will use examples and observation to illustrate my point.
I am a strong believer of…
I am a big fan of…

◎ 反對
I disagree with those who say that..
I strongly disagree with the statement that…
I don’t believe that …
I don’t like the view that…

◎ 列舉
For example,
For instance,
contain/include/ consist of
, such as…
A is made up of…
There are A, B, and C.
One — another — last—
First(ly)—Second(ly)—Then—Next—Finally—
First — Next —Third
For a start, —-. Second, ——. Third, —-
First of all — (In the first place)
People… Others… Some… Still others…
(sample usage) People just assumed that the general couldn’t stand the loneliness of retired life. Others blame his only son for neglecting his filial duty. Some sympathetic people even tried to create some kind of foundation and ask the him to be an adviser. Still others, who had published a collection of writings in honor of the general on his eightieth birthday, asked him, time and again, to give an oral account of his life as a historic testimony to a great age.
Some (models)…; others…; still others…
(sample usage) The methods of following patterns are as various as the patterns themselves. Some models provide especially effective sentence patterns; others lend themselves to organizational analysis; still others reveal an effective syntactical scheme. Whatever the method of using the model, the object -careful scrutiny of written material - remains.
.. a captain…; another captain….; a third captain…
(Kings 2 from the Bible / The NIV version)
Then he sent to Elijah a captain with his company of fifty men. The captain went up to Elijah, who was sitting on the top of a hill, and said to him, Man of God, the king says, ‘Come down!’ Elijah answered the captain, If I am a man of God, may fire come down from heaven and consume you and your fifty men! Then the fire fell from heaven and consumed the captain and his men.
At this the king sent to Elijah another captain with his fifty men. The captain said to him, Man of God, this is what the king says, ‘Come down at once!’ If I am a man of God, Elijah replied, may fire come down from heaven and consume you and your fifty men! Then the fire of God fell from heaven and consumed him and his fifty men.
So the king sent a third captain with his fifty men. This third captain went up and fell on his knees before Elijah. Man of God, he begged, please have respect for my life and the lives of these fifty men, your servants! See, fire has fallen from heaven and consumed the first two captains and all their men. But now have respect for my life!

◎ 結尾
To sum up,
To emphasize again
In this case
In such a context
As might be expected
In short,
Finally,
In a word,
In brief,
In conclusion
On the whole,
To conclude,
To summarize,

◎ 其他 (不同方式表述同樣事情)
The book begins with an introduction to the ABCs of Internet investing.
Chapter Two offers an examination of a single company, …
Chapter Three takes a close look at dot-com companies.
Chapter Four delves into businesses between businesses on the Net.
Chapter Five lays out the physical world of the “Internet backbone.”
Chapter Six looks at Internet proxy investments.
Chapter Seven addresses the stock market’s love-hate relationship with the Net.
Chapter Eight explores the world of mutual funds and venture capital.
Finally, Chapter Nine speculates on the post-PC era, when everything will be Internet-ready.

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头昏昏·~

The important is learn to use them.