The grammar pattern ほど～ない is another way to use the noun ほど, meaning 'extent' or 'degree'. It works by first presenting a standard or degree in part (A), and then using ない in part (B) to state that this standard has not been met. It can be translated as 'not as... as (A)' or 'not to the extent of (A)'. A direct translation would be 'to the extent of (A), (B) is not so'.

Typically, ほど follows a noun or a verb. The negative form ない will then be attached to a verb, an い-Adjective, or a な-Adjective to describe the subject in relation to the standard set by ほど.

• 試験(しけん)は考(かんが)えていたほど難(むずか)しくなかった。
  The exam wasn't as difficult as I had thought.
• 怒(おこ)るほどの問題(もんだい)じゃない。
  It's not an issue worth getting angry about. (This is not serious enough to get angry over)
• 日本語(にほんご)は英語(えいご)程(ほど)簡単(かんたん)ではないけど、面白(おもしろ)いから勉強(べんきょう)しています。
  Japanese isn't as easy as English, but it's interesting, so I'm studying it.
• この世界(せかい)に京都(きょうと)ほどきれいな町(まち)はない。
  There is no city in the world as beautiful as Kyoto.

In addition to showing that a certain degree wasn't met, this grammar is often used to compare two items. When used this way, it implies that item (B) cannot match the high standard set by item (A). This is very close to the English expression '(B) is not as ~ as (A)'.

• 先生(せんせい)ほど親切(しんせつ)な人(ひと)はどこにもいない。
  There's no one anywhere as kind as my teacher.