Translate into English in your own words. Thank you.

The definition of stress, orginally raised by Selye, states that 'all' external stimulus can bring human pressure, in addition that it can be positive or negative. The source of stress can be distinguished by three basic categories - discouragement, struggle and pressure.
Discouragement, a concept that when the efforts of an individual are restricted, regardless of the fact that this is formed during the way to success or the insufficiency of goals, anyway discouragement is arisen as an outcome. Generally an individual may not be able to handle this discouragement in a correct way, due to the reduced ability of self-criticism resulting from discouragement, giving a signal to the individual that failure is always the result, or just exposing his deficiencies.
Struggle, sometimes, stress may result from where one or more incompatible wants or motives simultaneously exist and thus choosing one of the two the alternative satisfaction must have to be forgone. Fundamentally, an individual engages in making choice, at the time of intiating, who would eventually encounter the struggle.
Pressure, is possible that it is created thereby the specified goals or special behaviors and conducts can be achieved. As stated in general, pressure would stimulate an individual in the course of acceleration of achievements, increasing efficiency or shifts between goals, whereas, under some conditions, a deep pressure may not be overcome with a limited pool of resources to deal with, and at the time of having extreme pressure some negative behaviours may be conducted for this situation.

The original definition of stress was introduced by Selye.He mentioned every single external stimulation will make people feel stressful even stress has been defined positive and negative.Stress is proceeded by 3 situations : frustration, conflict and pressure.(游恆山譯，民82)<--I dont know this book,sorry.......
1.Frustration: When people doing something and suffering the forces.The people will feel frustrated no matter the forces aims to pursuit of the goal or lack of properly goal.People usually feel difficult to cope with frustration.It is because frustration will drive you to depreciating yourself result in people eventually feel disappointed and shortage of abilities.
2.Conflict:Sometimes,stress is proceeded by two or more antipathic needs or motivation at the same times.However, if you merely meet one among your needs and get rid of the other.Basically,people have to make decision at this time.Eventually people would feel conflicted when making decision.
3.Pressure:Stress might be becoming the force to drive you to reach your specific goal or outstanding performance.Normally,pressure will force people to be accelerated,strengthen or change people orientations.However,people are unable to suffering a grave pressure.It would cause the unhealthy way to people.