suddenly ⇒ 天空忽然飘起了雪花。 Tiānkōng hūrán piāoqǐle xuěhuā. → All at once the sky filled with snow.

overlook ⇒ 易被忽略的细节 yìbèi hūlüè de xìjié → details that could be easily overlooked

suddenly ⇒ 远处的灯光忽而明，忽而暗。 Yuǎnchù de dēngguāng hū'er míng, hū'er àn. → The lights in the distance flickered on and off.

ignore

careless