It is free and extremely easy to use.

它是免费的，非常容易使用。

youdao

The good news, though: they are extremely easy to use.

不过好消息是它们易于使用。

youdao

It is extremely easy to use and requires no configuration.

它使用起来非常简单并且不需要配置。

youdao

All the functions are extremely easy to use thanks to extra-large buttons and extra-large letters.

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Then again, few predicted the massive popularity of camera-phones, but manufacturers did well by making them extremely easy to use.

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Finally, the company's entry-level digital camera models, the LUMIX S-Series, are extremely easy to use, making them ideal for consumers wanting an extremely intuitive experience.

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