cluck:
1. the sound a hen or chicken makes
2. express too much sympathy, anxiety or approval towards someone
She's very overprotective. She clucks over her son the minute he starts crying.

purr:
1. the sound a cat makes when it's contented
2. show your pleasure when speaking (in a sexy way)
'So open up your present and see what I got you' Marilyn Monroe purred.

bark:
1. the sound a dog makes
2. shout at someone forcefully
'Attention! Right, left! Right, left!' The army sergeant barked.

sting:
1. a small but painful injury, usually with a poison, that an insect makes by biting you
2. say something hurtful which upsets someone
When she criticised his work, it really stung him.

preen:
1. the way a bird cleans its feathers using its beak
2. feel very proud or satisfied with yourself because of something you've done or a quality you have
She's very vain and spends hours preening herself in front of the mirror before she goes out.

to be the cat's whiskers:
to be better than everyone else
He's thinks he's the cat's whiskers since he got promoted.

to keep the wolf from the door
to have just enough money to live on
It's a low-paid job but she had to take it to keep the wolf from the door.

to talk the hind legs off a donkey
to talk a lot for a long time
He never stops! He could talk the hind legs off a donkey!

to come home to roost
to return and make trouble for you
She didn't do any studying this term, just had a good time and went to loads of parties. Now the exams are here and it's all coming home to roost for her.

limping （跛行；一瘸一拐地走）
walking unevenly because of injury or pain in the leg

swelling（肿大；膨胀；增大）
becoming larger and rounder than usual

antibiotics （抗生素）
medicine that can destroy harmful bacteria

twice a day （每日两次）
two times every day