发烧
have a Fever
A fever is a higher-than-normal body temperature, one of the body’s natural responses to infection. A low-grade fever isn't usually a cause for concern, but a temperature 102°F and above should be treated.
发烧是身体对感染的自然反应之一，体温高于正常水平。低烧通常不需要担心，但102华氏度（大约38.9摄氏度）以上的体温应该得到治疗。
low-grade fever表示程度比较低的发烧，理解作低烧，而“发高烧”简单点可以说成 have a high fever，或者根据其本质就是体温很高表达成 have a high temperature。
退烧
“退烧”比较专业的一个词是动词defervesce /ˌdefə'ves/，它的意思就是退热，也可用它的形容词defervescing表示“退热的”。
比如，医生在交流病情时的会说
A: How's the patient?
病人情况如何
B: He's defervescing. Lytes, chest x ray, urinalysis were all normal.
他退烧了。电解质，胸部X光片，尿检结果都正常。
《急诊室的故事》第三季
也有很多口语中比较简单的搭配可以表达“退烧”，
比如
reduce fever
fever's down
fever's broken
The fever is gone.
Fever came down.
The heat is coming off.
而且，“退烧”可以理解为“体温降下来”
所以用英语说就是：
The temperature comes down.
更多相关表达
I've got a runny nose. / My nose is running.
我流鼻涕。
I've got a sore throat.
我嗓子疼。
I've been coughing day and night.
我一直在咳嗽。
I can't stop sneezing.
我打喷嚏打个不停。
I've got a temperature. / I'm running a high fever.
我发烧了。/ 我发高烧。
I've got a very bad headache. / This headache is killing me.
我头很痛。/我头快痛死了。
I feel sore and ache all over.
我觉得全身酸痛。
I am trembling with cold.
我冷得全身发抖。
I feel dizzy. / My head is swimming.
我头晕。/ 我头昏脑胀的。
I have a stuffy nose.
我的鼻子不通气。
好啦，今天的小知识点，你学会了嘛？
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