excessive sexual intercourse房劳
sexual intercourse in dream梦交
sexual intercourse poem房事诗
premarital sexual intercourse婚前性行为
sexual intercourse satisfaction性生活满意度
The third part is about the evolution of sexual intercourse.
第三部分是性交行为之演化。
参考来源 - 性权利视野下的强奸罪若干问题研究（研究生论文）N-UNCOUNT（不可数名词） Sexual intercourse is the physical act of sex between two people. 性交 [正式]
I have never had sexual intercourse with her and that is the truth.
我从未与她发生过性关系，而这是事实。