色厉内荏

色厉内荏	sè lì nèi rěn	lit. show strength while weak inside (idiom); appearing fierce while cowardly at heart / a sheep in wolf's clothing
色	sè	color / CL:种 / look / appearance / sex
色	shǎi	(coll.) color / used in 色子
厉	Lì	surname Li
厉	lì	strict / severe
内	nèi	inside / inner / internal / within / interior
荏	rěn	beefsteak plant (Perilla frutescens) / soft / weak