All the other naming rules apply to alkenes and alkynes too.

所有其他的命名规则也适用于烯烃和炔烃。

So, three words representing three different groups of organic compounds. Alkanes for all single bonds, alkenes if they contain double bonds, and alkynes if they contain one or more triple bonds.

因此，这三个词分别代表三类不同的有机化合物。烷烃是指所有键键的化合物；烯烃是指含有双键的化合物；炔烃是指含有一个或多个三键的化合物。

The fatty acid chains, they have long hydrocarbon chains, are what we're mostly concerned with here. They can be alkanes or alkenes, sometimes even rarely alkynes.

脂肪酸链有长的碳氢链，这是我们主要关注的部分。它们可以是烷烃或烯烃，有时甚至是罕见的炔烃。

You also learned a little bit about cis-trans isomerism and learned a few important reactions of alkenes and alkynes such as hydrogenation, halogenation, and polymerization.

你还一点关于顺反异构体的知识，并学习一些烯烃和炔烃的重要反应，如氢化、卤化和聚合。

They can be alkanes or alkenes, sometimes, even rarely, alkynes.

它们可以是烷烃或烯烃，有时甚至是罕见的炔烃。

All the other naming rules apply to alkenes and alkynes too. For instance, the main carbon chain, the longest one, is numbered in such a way that the various components, including the double bond, have the lowest numbers possible.

所有其他命名规则同样适用于烯烃和炔烃。例如，主碳链（即最长碳链）的编号方式应使包括双键在内的各个组成部分有尽可能低的编号。

How do you remember which is which? Well, I have a trick that I use. There's only one letter changing here. A in alkanes changes to E for alkenes and then to Y for alkynes.

如何记住它们各自代表什么？我有个小技巧。这里只有一个字母在变化：烷烃（alkanes）中的 A 变烯烃（alkenes）中的 E，再变炔烃（alkynes）中的 Y。

If they've got a double bond, we call them alkenes, and those with triple bonds are alkynes.

如果它们含有双键，我们称它们烯烃，而含有三键的则称炔烃。

That may not sound like a big deal at first, but alkenes and alkynes don't have that kind of freedom, and that simple fact has a huge effect on their properties.

起初这听起来可能没什么大不的，但烯烃和炔烃并不备这种自由度，而这一简事实对它们的性质产生巨大影响。

There's only one letter changing here: A in alkanes changes to E for alkenes and then to Y for alkynes.

这里只有一个字母在变化：烷烃中的A变成烯烃中的E，然后再变成炔烃中的Y。

That may not sound like a big deal at first, but alkenes and alkynes don't have that kind of freedom, and that simple fact has a huge affect on their properties.

这乍一听可能不算什么大不的事，但烯烃和炔烃就没有这种自由度， 这个简的事实对其性质产生巨大影响。

Thus, no isomers with alkynes. Phew. OK I'm done describing for the moment.

因此，炔烃没有异构体。松口气。好吧，我暂时先描述到这儿。

Alkenes can be made into alkanes and alkynes can become either alkenes or alkanes depending on how many atoms are added.

烯烃可以转化烷烃，而炔烃则可以根据添加的原子数量变成烯烃或烷烃。

If you paid attention, you learned that hydrocarbons with double bonds are called alkenes and those with triple bonds are called alkynes and that the naming rules are the same as for alkanes.

如果你注意听，你应该知道带有双键的碳氢化合物称烯烃， 带有三键的称炔烃， 而且它们的命名规则与烷烃相同。

So three words representing three different groups of organic compounds: alkanes for all single bonds, alkenes if they contain double bonds, and alkynes if they contain one or more triple bonds.

所以三个词代表三种不同的有机化合物组：烷烃表示全键，烯烃表示含有双键，炔烃表示含有一个或多个三键。

The triple bonds in alkynes, meanwhile, are composed of 1 sigma bond and 2 pi bonds for a total of 3 bonds.

炔烃中的三键由1个σ键和2个π键组成，总共3个键。