Although/Though he is often late, he is a good student.虽然他经常迟到,他还是个好学生。
Although/Though he is the secretary, he must obey the rules.虽然.....,他还得遵守规定。
Although / Though he should often be late, he is a good student.即便/就算他经常迟到,他还是个好学生。(既有让步含义,又有条件含义)
Although / Though he should be secretary, he must obey the rules.即便/就算..,他还得遵守规定。(有让步,还有条件)