[填空题]If I should fail, I (try)______again.

[填空题]If I should fail, I (try) ______ again.

[填空题]If the measure of vaccine should fail, the only backup would be ______.

[填空题]Even if you should fail to persuade him，______________________________(也不要失望)．

[单项选择]"Humans should not try to avoid stress any more than they would shun food, love or exercise." said Dr. Hans Selye, the first physician to document the effects of stress on the body. While here’s no question that continuous stress is harmful, several studies suggest that challenging situations in which you’re able to rise to the occasion can be good for you.
In a 2001 study of 158 hospital nurses, those who faced considerable work demands but coped with the challenge were more likely to say they were in good health than those who felt they couldn’t get the job done.
Stress that you can manage may also boost immune(免疫的)function. In a study at the Academic Center for Dentistry in Amsterdam, researchers put volunteers through two stressful experiences. In the first, a timed task that required memorizing a list followed by a short test, subjects believed they had control over the outcome. In the second, they weren’t in control: They had to sit through a gory(血淋淋的)video on surgical
A. the video was not enjoyable at all
B. the outcome was beyond their control
C. they knew little about surgical procedures
D. they felt no pressure while watching the video