1.可以.
2.固定句型It's up to sb to do sth一般有两种意思：
1）由某人决定去做某事
如：It's up to you to decide how to get there.
由你来决定怎样到达那儿.
2）做某事是某人的义务/职责/责任
如：It's up to her to lock the door.
锁门是她的职责./锁门由她来负责.