Be as sick as a dog 病得很重
Sally was as sick as a dog and couldn't go to the party.
Be as blind as a bat（蝙蝠）
I've worn glasses for 20 years, so I'm as blind as a bat now.
Be as busy as a beaver （海狸）
Between working two part-time jobs, volunteering on the weekends, and looking after his little brother, Sam's been as busy as a beaver this summer.
Be as stubborn as a mule（驴）
If you tell her what to do, she won’t do it because she’s as stubborn as a mule.
Be as drunk as a skunk（臭鼬）
Do you remember last night at all? You were as drunk as a skunk!