XX如YY/ 其XX如YY (more idiomatic, usually contains four characters)
有如XX般YY/ 如XX般YY (more literary)
跟XX一般YY/ 像XX一樣YY (more colloquial)
XX得跟YY一般/ XX得像YY一樣 (even more colloquial)
Example:
1a. 蠢如豬牛 - stupid like pig and cow
1b. 兇狠如狼 - vicious like a wolf
1c. 其蠢如豬 - stupidness like a pig's
1d. 其狠如狼 - viciousness like a wolf's
2a. 如豬牛般愚蠢 - as stupid as pig and cow
2b. 如豺狼般兇狠 - as vicious as a wolf
3a. 跟豬牛一般愚蠢 - as stupid as pig and cow
3b. 像豺狼牛一樣兇狠 - vicious like a wolf
4a. 愚蠢得跟豬牛一般 (so foolish it is like pig or cow)
4b. 兇狠得像豺狼一樣 (so vicious it is like a wolf)