Another 2+2 like the i3, the i8 concept was equipped with impractical butterfly doors for the show that are unlikely to show up on the production version.

I8也采取了和i3一样的2+2设计，车展上展出的i8概念车安装了中看但不实用的蝴蝶式车门，不过这种车门估计不会出现在量产版上。

youdao

When both doors are open at the same time, they form a butterfly, a beautiful figure, which is spectacular for its size.

当两个通道在同一时间打开时，桥梁像一只巨大的蝴蝶，非常壮观。

youdao

It has butterfly doors, a carbon-fiber body and a roof-mounted air intake that spins as the car moves.

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Conceptually similar to GM's AUTOnomy fuel-cell concept of 2002, the i8 like its urban-EV sibling, the i3 is radically different in one respect: BMW says it is actually going to build it, virtually as it appears in concept-car form, complete with its semitransparent body panels, butterfly doors, glowing blue grilles and laser headlights.

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