12. _______to zoos in Beijing and other cities, the elephants are reported _______well. I'm glad to
A. Having been sent, to settle B. Sent, to have settled down C. Sent, to be settled D. Being sent, to have settled选那一项，是不是Having been sent；to have settled down比较合适，关键是第二个空用不用被动
having been done 和done作状语用时，基本上可以换用，都表示被动和完成。 当状语中有表示一段时间或次数的词时，就只能用现分的完成被动式，不用过分。 选择B，也能用：Having been sent；to have settled down settle down是个不及物动词词组，不用被动。