Good student as he is, ...
结构︰名词＋as＋主词＋be 动词，...
说明︰此句型意为"虽然...，但是..."。等於"though＋<主词>＋be <动词>＋<名词>"。若 be <动词>之后的<名词>是单数，移至句首后<冠词>要省略。
Good students as they were (=Though they were good students), they sometimes erred.
虽然他们是好学生，偶而也会犯错。
Good student as he is (=Though he is a good student), he sometimes makes mistakes.
虽然他是好学生，偶而也会犯错。
Coward as he is (=Though he is a coward), he can't bear such an insult.
虽然他是懦夫，却无法忍受这样的侮辱。