Cause and Effect outline

Topic: what is the positive and negative side of using headphone?

Thesis statement: Too much using of headphone leads to a lot of negative effect including hearing problem, traffic accident and lower efficiency.

1^st topic sentence: High volume of headphone causes irreversible damage to our hearing ability.

Supporting details: Eardrum is actually very fragile and the long-term using of headphone with a high volume forces the eardrum to work at a high level. Eardrum will then become ineffective.

2^nd topic sentence: Using headphone to listen to music while walking on the street is the cause of many traffic accidents.

Supporting details: People cannot hear the sound from outside like the alarm of the cars clearly when they cross the street if they are using headphone. They will not even be aware that there may be a truck coming to them.

3^rd topic sentence: Using headphone during work or studying blocks the noise from outside while it will increase our efficiency.

Supporting detail: The noise from outside, not like the music coming from the headphone, will distract our attention e.g. we are always distracted by someone others talking about interesting things, and headphone will then make them impossible to coming in.