by 1921 in sexual sense, from fore- + play (n.); Freud's Vorlust was translated earlier as fore-pleasure (Brill, 1910). A more direct translation from the German would be thwarted by the sense drift in English lust (n.). Earlier as a theatrical term:
In fact the poem which Mr. Brooks has translated is but the "prologue to the swelling theme," the fore-play to the actual drama of Faust. ["The Christian Examiner and Religious Miscellany," Jan.-May 1857]
1. Testicle foreplay was the weak point of our sex last night, right?
2. Russian boo - boos , you go for some basic foreplay, they'll detail your car.
俄罗斯妹, 你做好基本前戏, 她们会把你[照料]得很好.
3. Foreplay is a way to prepare your lover and yourself for sex.
4. House: Is it true what they say about Jewish foreplay?
那他们说的犹太人的前戏是真的 吗 ?
5. You understand that this is foreplay, this is the creativity.