All factors having been taken into consideration,they began to do something to improve the situation.你的题目抄错了,不可能about be situation语法不对!考点有动词语态时态和独立主格.
all factors所有因素,当然是被考虑,语态为被动.（take sth.into consideration,考虑...）因为采取措施在思虑之后,所以被考虑这动词用完成时.在这里All factors having been taken into consideration是独立主格,（本句真正主语为人they）作时间状语.=After all factors were taken into consideration,they began to do something to improve the situation.此时因为有after,不必用完成时.想知道更多独立主格的话可以查语法书或百度,这里说不太清楚.