〜ほど／〜くらい（程度）

Used to show the degree of a state or action by giving a concrete, often exaggerated comparison: 'so ~ that ...'. ほど tends to sound a little stiffer and is common in writing, while くらい/ぐらい is more conversational and often describes a low or trivial degree as well. Note the difference from the quantity use of ぐらい ('about'), and remember that here the clause before ほど/くらい explains how extreme the preceding state is.

• お腹が痛くて、歩けないほどだった。

  おなかがいたくて、あるけないほどだった。

  My stomach hurt so much that I couldn't even walk.

• 彼の日本語は、日本人と間違えるくらい上手だ。

  かれのにほんごは、にほんじんとまちがえるくらいじょうずだ。

  His Japanese is so good you'd mistake him for a Japanese person.

• 今日は山が見えるほど空気がきれいだ。

  きょうはやまがみえるほどくうきがきれいだ。

  The air is so clear today that you can see the mountains.