我在美国生活了九年了，希望我的建议对你有用。

想“委婉”表达，你可以说对方对你很重要：You've become an important person of mine （或者 in my life）。可以赞扬对方的漂亮：You are pretty. You are beautiful. 或者告诉她你跟她一起很开心：It's fantastic working with you.或者告诉她你愿为她做一切事情：I do whatever you want for you. I'd do anything that pleases you.