Adding the prefix for created forlorn, meaning to be lonely or sad.

加上“for”就构成了“forlorn”，意为“孤独的”或“悲伤的”。

For example, ’Un is a very common prefix in the English language.’

例如，在英语语言中un是一很常见的。

Students could focus on prefixes that are used to give a word an opposite meaning.

学生很有可能会关注词语的获得相反的意思。

In metric units, which of these prefixes means " billion" ?

以下的公制单位中，哪一表" 十亿" ？

No, Neil, though it does have the same prefix – 'micro'.

不，尼尔，虽然它们有相同的" 微" 。

As you can see, both words have the same prefix that means equal.

如你所见，这两有 意味着「均等」的首。

Prefixes are letters we add to the beginning of a word.

是我们添加到单词开头的母。

Adding a prefix to a word makes a new word with a new meaning.

给单词添加一就会造就一具有新含义的新单词。

So we create new words by adding prefixes and suffixes to the root word.

我们通过向词根添加和后创造新词。

Or he's very 'pro' something -- well they're prefixes which have suddenly become different words.

或者是他非常‘pro’...这些是可以使单词突然变得不同的。

These prefixes are in order of thousand, million, billion, and trillion with giga denoting billion.

上述按顺序分别表千、百万、十亿和万亿，其中giga表十亿。

The prefix in can change the meaning of a word into its opposite.

in 可以把一词的意思变成它的反义词。

IN- is a negative prefix that means no or not.

IN-是一否定，表没有或没有。

But in- is also a common negating prefix, leading to the second interpretation.

但是in-也是一常见的否定，于是引出了第二种释义。

It's biathlon, so I hear the phrase prefix bi, which means two.

它是冬季两项，所以我听到“bi”这词，意思是两项。

This re- prefix means to do something again.

这“re-”表再次做某事。

The prefix of this word, kata, means “down.”

这的首意思是“下”。

So we have " usual" means ordinary, I put the prefix in, it means not ordinary.

我们有“寻常的”，意思是普通的，我把放进去，就变成不寻常了。

She uses the prefix hyper to say that there is too much of a certain quality.

她使用“hyper”表某种特质太多。

Ah yes – and the word 'micro' used as a prefix, indicates that something is small.

啊，是的。还有" 微" 这词用作，表某物是小的。