她用胳膊发出左转弯信号。

She given a left turning signal with her arm.

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左转弯时，驾驶员要提前发出转向信号，转向时尽可能靠道路中心，为后车和右转弯的车提供方便；

Turn left, the driver should make turn signal, to as far as possible by the road center, for after the car and right turn the car to provide convenient;

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