I looked at the moon and murmured to myself: Oh, moon, female friend of ours, how many people sing of you; how many people write about you.
我望着月亮喃喃自语:月亮,朋友,多少人把你歌唱,多少人为你写作。
By appropriate, I mean, a female friend might love it if you rub her shoulders, but might be uncomfortable with something more 「romantic,」 like caressing her hair and cheek.