Apple updated the aluminium unibody MacBook Pro line to include 13-inch, 15-inch and 17-inch models featuring up to 40 per cent longer battery life.

苹果公司更新了拥有铝制机身的MacBook pro产品线，新产品包含13寸、15寸、17寸三种规格的产品，电池续航时间较以前有40%的提高。

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The 15-inch Series 9 is far skinnier and lighter than the MacBook Pro, then, but it matches the MBP in build quality, thanks to a rock-solid unibody aluminum chassis and some funky aquamarine keyboard backlights.

ENGADGET: Apple MacBook Pro with Retina display review (mid 2012)