"尽管我的英语成绩不好"用英语可以说成"Although my Engpsh grades are not good"。
"Although"是一个连词，意思是"尽管"，用来连接两个相反的事实或两个相反的观点。例如：
Although it's raining, I'm still going to the park. (尽管在下雨，我还是要去公园)
Although he's very rich, he's not very happy. (尽管他很有钱，但他不是很快乐)
"My Engpsh grades are not good" 是一个完整的句子，意思是"我的英语成绩不好"。其中 "My" 是形容词性物主代词，表示“我的”； "Engpsh" 是名词，表示"英语"；"grades" 是名词，表示"成绩"， "not good" 是副词性短语，表示"不好"。