The most obvious and most reliable way of avoiding pregnancy is complete abstinence from coitus.
避免怀孕最显而易见和最可靠得方法是禁绝性交。

Re aching org asm long after the beginning of coitus is a common male dysfunction.
性交长久以后才达到性高潮是男性常见的性功能障碍。

mucoitinsulphuric acid.
硫酸黏液素

They developed an artificial coition machine.
他们研制出一种仿真交媾仪

DracoIt is good that an Asian company and a European company are cooperating.
亚洲公司和欧洲公司合作, 这是一件非常好的事。

Basic coital position.
基本性交体位

Coitus interruptus is not a very reliable method of birth control.
体外排精避孕法不是一种可靠的节育方法。

postcoital bleeding.
性交后出血

By13 days5 minutes after coitus, the head process invaginating in the primitive pit move straight forward in cephalic derection to form the notochordal cord.
交配后13时5分，原窝底部的头突向前延伸形成管索管。

coital exanthema.
水疱性媾疹

Coital sexual orgasm.
性交性高潮

coital vesicular exanthema.
水疮性媾疹

Lateral recumbent coital position
侧卧式性交体位

Unclassified coital position
未分类的性交体位

Frontal sedentary coital position
正面坐式性交体位

Male succumbent coital position
男性从属式性交体位

The next step to coital climax involves intense genital friction.
达到高潮的下一步便是激烈的阴部摩擦。

indulgence in drinking and coition resulting in consumptive disease
酒色过度，积损成劳

The vagina receives the penis during coitus.
阴道在性交过程中容纳阴茎。

coitus posterior.
后横位性交

To engage in coitus or sexual intercourse.
进行交媾过性交。

normal libido, coitus, and climax
正常性欲, 性交及性欲高潮

You have it wrong. coitus means to make babies
你搞错了吧，交配是造人的意思

Their meeting is usually about as a result of coitus.
精卵相遇通常是性交得结果。

This, in turn, has increased their enjoyment of coitus.
继而，这又增添了他们性交合的乐趣。