Teacher burnout（倦怠） and student stress may be linked，according to a University of British Columbia study．The study is the first of its kind to examine the connection between teacher burnout and students""cortisol levels（可体松水平），which are a biological indicator of stress．
Researchers collected saliva（唾液）samples from over 400elementary school children and tested their cortisol levels．They found that in classrooms in which teachers experienced more burnout，or feelings of emotional exhaustion，students""cortisol levels were elevated．Higher cortisol levels in elementary school children have been linked to learning difficulties as well as mental health problems．
"This suggests that stress spreading might be taking place in the classroom among students and their teachers，"said Eva Oberle，the study""s lead author．Indeed，the relationship between student stress and teacher burnout is a chicken and egg question．It is unknown what came first-elevated cortisol or teacher burnout．We consider the connection between student and teacher stress a cyclical problem in the classroom．"
Oberle said a stressful classroom climate could be a result of inadequate support for teachers，which may impact teachers""ability to effectively manage their students．A poorly managed classroom can contribute to students""needs not being met and increasing stress．This could be reflected in elevated cortisol levels in students．
Alternatively，stress could originate from students，who may be more challenging to teach because of increases in anxiety，behavioural problems，or special needs．In this scenario，teachers could feel overwhelmed and report higher levels of burnout．
"Our study is a reminder of the systemic issues facing teachers and educators as classroom sizes increase and supports for teachers are cut，"said Oberle．
"It is clear from a number of recent research studies that teaching is one of the most stressful professions，and that teachers need adequate resources and support in their jobs in order to battle burnout and alleviate stress in the classroom，"said UBC education professor Kimberly Schonert-Reichl，the study""s co-author and director of HELP．"If we do not support teachers，we risk the collateral damage（附带损害） of students．

63．Which is the best title of the passage？___
A．How to Relieve Stress in the class
B．A puzzling Question of Egg and Chicken
C．The Most Stressful Profession in the world
D．The Link Between Students Stress and Teacher Burnout
64．Paragraph 4and paragraph 5are intended to make it clear that___．
A．teacher burnout may be cause of the elevated cortisol levels in students
B．the connection between students and teacher stress is a cyclical problem
C．students with higher stress level are more likely to have learning difficulties
D．student""behavioural problems may result in teacher""s higher level of burnout
65．According to the writer，many British teachers face the problem that___．
A．teacher are not well trained to deal with students""problems．
B．teachers""income increases but teaching resources are cut
C．there""re more students in each class and less support for teachers
D．there is a widening gap between students""need and teachers""ability
66．Which of the following statements is FALSE？___
A．The more burnout teachers experience，the higher cortisol levels in students．
B．Adequate support may help teachers manage students more effectively．
C．Students will benefit as a result of reduced teacher burnout．
D．High cortisol level indicates high level of burnout．

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