Usage note
发烧表示身体温度变高，可能生病了。
fā shāo biǎo shì shēn tǐ wēn dù biàn gāo， kě néng shēng bìng le。
发烧 means the body temperature is high and you may be sick.
Context note
发烧常出现在健康、看医生和请假时。
fā shāo cháng chū xiàn zài jiàn kāng 、 kàn yī shēng hé qǐng jià shí。
Fever often appears in health, seeing a doctor, and taking sick leave.
5 examples
我发烧了。
wǒ fā shāo le。
I have a fever.
他昨天发烧。
tā zuó tiān fā shāo。
He had a fever yesterday.
如果发烧，要去看医生。
rú guǒ fā shāo， yào qù kàn yī shēng。
If you have a fever, you should see a doctor.
妹妹有点发烧。
mèi mei yǒu diǎn fā shāo。
My younger sister has a slight fever.
发烧的时候要多休息。
fā shāo de shí hòu yào duō xiū xi。
When you have a fever, you should rest more.
5 mini stories
昨天晚上我有点发烧，所以今天在家休息。
zuó tiān wǎn shàng wǒ yǒu diǎn fā shāo， suǒ yǐ jīn tiān zài jiā xiū xi。
Last night I had a little fever, so today I am resting at home.
妹妹发烧了，妈妈带她去看医生。
mèi mei fā shāo le， mā ma dài tā qù kàn yī shēng。
My younger sister had a fever, and Mom took her to see the doctor.
发烧的时候不要乱跑，要多喝水。
fā shāo de shí hòu bú yào luàn pǎo， yào duō hē shuǐ。
When you have a fever, do not run around; drink more water.
老师说如果发烧了，就要告诉家长。
lǎo shī shuō rú guǒ fā shāo le， jiù yào gào sù jiā zhǎng。
The teacher said if you have a fever, you should tell your parents.
吃完药以后，他觉得舒服一点了。
chī wán yào yǐ hòu， tā jué de shū fú yì diǎn le。
After taking medicine, he felt a little better.
Mini dialogue
不舒服
A
老师，我有点不舒服，好像发烧了。
Lǎoshī, wǒ yǒudiǎn bù shūfu, hǎoxiàng fāshāo le.
Teacher, I feel a bit unwell. I think I have a fever.
B
让我看看。你的头很热，可能真的发烧了。
Ràng wǒ kànkan. Nǐ de tóu hěn rè, kěnéng zhēn de fāshāo le.
Let me see. Your head is very hot. You might really have a fever.
看医生
A
妈妈，我发烧了，头很疼。
Māma, wǒ fāshāo le, tóu hěn téng.
Mom, I have a fever and a bad headache.
B
别担心，我们马上去看医生。
Bié dānxīn, wǒmen mǎshàng qù kàn yīshēng.
Don't worry, let's go see a doctor right away.
Related words and contrasts
related
感冒
gǎnmào
catch a cold
感冒 often causes 发烧 (fever).
related
生病
shēngbìng
get sick
发烧 is one way of 生病 (being sick).