但他从未放弃英语

He didn't pass the exam, but he did not give up.或者Although he didn't pass the exam, he did not give up.

However, he did not give up and eventually achieved success.

however, he didn't give up. In the end, he succeeded.

However, he never give up. Consequently, he succeeded.其中这里的Consequently也可以用Finally，即表示最后他成功了。如果要再文雅一点，那么可以把he succeeded换成he made a success.呵呵，看你喜欢了。

However, he did not give up,therefore, he succeeded

In spite of the fact that he hasn't pass the exam, he didn't give up.虽然他没有通过考试，但他并没有放弃。

He did not pass the exam, but he did not give up studying english.或 though he did not pass the exam, he did not give up englisg study.