Yahweh causing much rain to fall in order to make the crops grow is spoken of as if Yahweh were opening windows in heaven through which he pours down rain. See how you translated this in [2 Kings 7:2](./01.md). Alternate translation: "even if Yahweh were to cause much rain to fall from heaven" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The captain asks this question to express his unbelief. This question can be translated as a statement. See how you translated this in [2 Kings 7:2](./01.md). Alternate translation: "this could never happen!" (See: [[rc://en/ta/man/translate/figs-rquestion]])
The phrase "with your own eyes" emphasizes that the captain will certainly see the things that Elisha prophesied. See how you translated this in [2 Kings 7:2](./01.md). Alternate translation: "you yourself will watch these things happen" (See: [[rc://en/ta/man/translate/figs-synecdoche]])