As I know, the verb 나가다 means "to leave", "to get out", "to exit".
I met many usages of this verb added to some other verbs, but I can't figure out it's functionality.
자주통일의 앞길을 힘차게 열어나가자! (open + get out)
조국과 혁명앞에 다진 맹세를 변함없이 지켜나가도록 하여야 합니다. (defend + get out)
Also, I found a form 화해나가다.
What do these sentences mean? How does the verb 나가다 affect on the verbs 열다, 지키다, 화하다?