I am of the opinion that…
I would take view that…
第二段主题句：
The explanation for this phenomenon may include several factors and I will express only a few of the most important ones.
The reason why I cannot accept the job offered may include several factors and I will express only a few of the most important ones.
三个层次：
first of all;
in addition;
furthermore.
first and foremost,
besides,
last but not least
In the first place
In the second place
In the third place
个人层面
1.个人的兴趣爱好
Doing something is of great interest, for it adds color to the dull routine of everyday life.
(02.6)A great many university students are fond of surfing online.
Surfing online is of great interest, for it adds color to the dull routine of everyday life.
As a result, a great many university students indulge themselves in the internet.
2.丰富/提高生活质量
Something helps to improve the quality of people’s lives.
例：The use of private cars helps to improve the quality of people’s lives.
3.运动健身
Regular exercises benefit both the body and mind.
4.社会责任感
Doing something will develop one’s strong sense of duty.
5.参加活动，培养团队合作精神
Participating in activities can develop a sense of team spirit and cooperation.
6.人际关系
Doing something will enhance mutual understanding.
例：Talking with my roommates will enhance mutual understanding.
7.个人能力和职业发展
Doing something will develop one’s capability and helps one to start a new career.
例：Working hard will develop one’s capability and helps one to start a new career.
Getting proper training will develop one’s capability and helps one to start a new career.