反过来也是可以的啊

score=85

if score<60:

        print "failed"

elif score <80:

        print "passed"

elif score<90:

        print "good"

else:

        print "excellent"

顺序要有分明

score = 85
if score >=90:
    print 'excellent'
elif score >=80:
    print 'good'
elif score >=60:
    print 'passed'
else:
    print 'failed'