Upon learning of systematic discrimination experienced by African Americans in the military, he called on them to "return fighting" from the war.
在了解到非裔美国人在军队中遭受的系统性歧视后，他呼吁他们从战争中“回复斗争”。
2
Impressively, the learning of the second group also was comparable to that of a third group that for a week practiced the pitch-discrimination target task for 40 minutes per day.
第二组的学习成果与第三组相似，而第三组是连续一星期每天训练40分钟，这非常令人震惊。
3
Using the same rapid visual discrimination task, we found that only with more than six hours of sleep did people's performance improve over the 24 hours following the learning session.