grading up meaning in English

级进杂交
进级杂交
提高品位

I could get my grades up enough to go to brown with you
我可以得到足够高的评级，能和你一起进入brown
Scientists have been trying to find methods of grading up cattle to provide better meat for the market
科学家们一直在想法子提高牲畜的质量以向市场提供更好的肉食。
I see . well , i ' m sure your folks will be glad to see you . hope you ' ve been keeping the grades up
这样啊！嗯，相信你爸妈一定很高兴见到你，希望你在学校成绩表现良好。