性行為的基本類型

首次性交合

儘管與其它性交形式比較起來，要開始進行性交合簡直是再容易不過了，但是要完全達到相互滿足，在任何情況下或任何時候都幾乎是不斷練習和反復體驗的結果。尤其青年人經常趨向於期待太多和過於迫不及待。大多數男孩和女孩在實際發生好久以前就想著、夢著、甚至談論著他們的第一次性交合，而他們的希望、擔心和幻想可能終將會與真實體驗有一定的差距，會有幾分失望。夢想與現實脫節的一個極好的例子通常是女孩的“破膜（defloration）”的重大價值問題，即女孩的處女膜破裂。當然，處女膜可能因月經棉止血栓、自娛或手交或一些運動的結果而破裂。儘管如此，在大多數女性，處女膜直到被陰莖首次插入陰道之前的那一刻，程度不等地仍會保持完整。許多青少年就這個時刻有誇張和不切實際的觀念，事實上，也許預先提心吊膽地擔心它的完整性有了一些年頭。因而，男孩也許懷疑他的陰莖是否會以任何方式勃起到足夠的硬度以穿透這層處女膜，而女孩也許會預料有某種帶來疼痛的身體傷害。不過，所有這些擔憂都缺乏足夠的理由。因為處女膜正常情況下很容易破裂，所以對於男性來說，並不需要使用蠻力和採取粗暴。當然，漸進的、緩慢的和溫柔的挺進才是最好的做法。另一方面，女性可能會體驗某種不適和有些微的出血，但是不必擔心有任何大的疼痛。只有在罕見的例子裏，處女膜確實證明過厚而難以穿過，不過，醫生在他的診室裏通過簡單的外科處置就能夠輕易地解決這個問題。

處女膜的各種各樣形狀

處女膜在個體之間存在差異。它也許幾乎完全地封閉著開口，或也許有數個小孔，甚或只有一個大孔。後者也許在實際仍保持童真的時候就已經破裂。

Various shapes of the hymen
The hymen differs from one female to another.
It may almost totally close the vaginal opening, or it may have several small or even one large hole in it.In the latter case, it may seem broken when it is actually still intact.

2. Heterosexual Intercourse: Genital Intercourse

Coitus

First Coitus
It is easy enough to start coitus, but, as with all other forms of sexual intercourse, complete mutual satisfaction is almost always the result of practice and experience. Young people especially often tend to expect too much too soon. Most boys and girls think, dream, and even talk about their first coitus long before it actually occurs, and their hopes, fears, and fantasies can turn the eventual real experience into something of an anticlimax. A good example is the great significance that is usually attributed to a girl's "defloration", i.e., the rupturing of her hymen. The hymen may, of course, be ruptured by the use of tampons, by masturbation, or as a result of certain athletic activities. Still, in most females it remains more or less intact until that moment when a penis is first inserted into the vagina. Many adolescents have exaggerated and unrealistic ideas about this moment and may, in fact, worry about it years in advance. Thus, a boy may wonder if his penis will ever be hard enough to penetrate the hymen, and a girl may anticipate some painful physical injury. However, none of these worries are justified. There is no need for males to be tough and brutal because the hymen normally ruptures very easily. Indeed, a gradual, slow, and gentle approach is best. Females, on the other hand, may experience some discomfort and slight bleeding, but they need not fear any great pain. Only in very rare cases does the hymen prove to be too thick for penetration, but then a physician can easily solve the problem in his office by a simple surgical procedure.