现在分词作宾语补足语的时候可以在前面加as,比如：

(1) He described the picture as expressing the dream of mankind.

(2) They considered me as having done my best.

那么过去分词作宾语补足语的时候可以不可以在前面加as呢？比如这句

James Boswell, his biographer, described the garret where Johnson worked as ' fitted up like a counting house' with a long desk running down the middle at which the copying clerks would work standing up.