On seeing the sign __,the driver knows there is a sharp right-hand bend ahead,
问题描述：
On seeing the sign __,the driver knows there is a sharp right-hand bend ahead,
He must drive his car carefully.
答
句意：看见这个“”标志,司机知道前方右手边有个急转弯的地方.他必须小心驾驶.
填“slow down“（减速慢行）,“Look out”（小心）,“Danger”（危险）之类的告示语吧.