是 under a big stress 还是 under big stress?

是on stress还是under stress? Under a big tree ____ ,half asleep. Thay sat down under a big tree they are------tea under a big tree she sat down under a big tree Sometimes when people are under a lot of emotional stress,th Under the big tree ____. Only then did she realize the stress he was under. when are you under stress?what make you feel stressed some people under stress tend to bring their potential into Do you work well under stress or pressure? the man was under so much stress that he finally_____