HTML5是一种对象较新的规范，因为浏览器支持是非常有限的(在编写本教程时)。

HTML5 is a relatively young specification, and as a result, browser support is quite limited (at the time of writing).

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HTML V5 规范的编写保持了和浏览器厂商的深入沟通，始终考虑到实现的问题。

The HTML V5 specification was written using good communication with browser vendors, keeping implementation concerns in mind.

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如果不是，那可能是浏览器缓存了映像规范。

If not, it is possible that the image specification is cached in your browser.

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