The vehicle ahead is turning left, turning around or overtaking another vehicle ahead;

前车正在左转弯、掉头、超车的；

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When overtaking on a road without a Central Line, the driver should turn on the left-turn signal and overtake from the left side of the vehicle to be overtaken.

在没有中心线的道路上超车时，应开启左转向灯，从被超车左侧超越。

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The lanes will cut into the pavement around some bus stops to allow cyclists to undertake stationary buses on the left, rather than overtaking them on the right and having to move into traffic.

BBC: Consultation on cycle superhighway extension plans