Expression and い adjective
うんがいい
最近みょうに運がいいんだよな。
I’ve been really lucky lately for some reason.
こんな美人のよめさんもらって、お前って本当に運がいいな。
You are so lucky to have such a beautiful wife.
日本語の授業でAが取れたんだけど、ただ単に運がよかっただけだと思うの。
I got an A in Japanese, but I think I was just lucky.
The いい portion means "good." So, when what you carry is good you are lucky. Just think of it in terms of luck being a physical item you carry in your hands. Now imagine yourself carrying it. Now think to yourself "what I'm carrying is good, it's lucky!"
The reading for the kanji in this vocab is the same as the one you learned with the kanji, meaning you should be able to read this.