读某区域示意图，回答问题。

如图①，△ABC的角平分线BD、CE相交于点P.
（1）如果∠A=70°，求∠BPC的度数；
（2）如图②，过P点作直线MN∥BC，分别交AB和AC于点M和N，试求∠MPB+∠NPC的度数（用含∠A的代数式表示）；

①                   ②             ③            ④
在（2）的条件下，将直线MN绕点P旋转.
（ⅰ）当直线MN与AB、AC的交点仍分别在线段AB和AC上时，如图③，试探索∠MPB、∠NPC、∠A三者之间的数量关系，并说明你的理由；
（ⅱ）当直线MN与AB的交点仍在线段AB上，而与AC的交点在AC的延长线上时，如图④，试问（ⅰ）中∠MPB、∠NPC、∠A三者之间的数量关系是否仍然成立？若成立，请说明你的理由；若不成立，请给出∠MPB、∠NPC、∠A三者之间的数量关系，并说明你的理由.

    What do you do at the weekends? Some people like to1 at home. But others like to go for a walk2 play football. My friend Jack works hard in a factory on3. At the weekends he always 4 different things. On Saturday he5 his car and on6 he goes with his family to a village by car. His uncle and aunt have a farm there. It's not a7 one, but there's always8 to do on the farm. The children help with the animals and give them their9. Jack and his wife help in the field. At the end of the day, they are all10 and want to have a big meat very much.