Investigators have a____ enough evidence to put that thief in jail for many years.
小强的爷爷平时戴眼镜，看书时却要摘下眼镜：奶奶平时不戴眼镜，看书时却要戴上眼镜．请判断爷爷和奶奶戴的眼镜分别是（ ）
“天苍苍，野茫茫，风吹草低见牛羊”是对以下哪个少数民族聚居的草原景观的描述
