Large cerebral infarction in the left cerebral hemisphere may be characterized by language impairment, hemiparesis of the right side of the limbs, and coma. 1. Language disorder: the left side of the brain is usually the dominant hemisphere of the language center. If there is a large infarction in the left hemisphere, the patient’s language function will usually be seriously impaired, and the patient may suffer from aphasia, dysarthria and other symptoms, and be unable to carry out normal language communication. 2. Right hemiplegia: The left side of the brain is mainly responsible for the motor function of the right side of the limbs. When the left side of the brain is infarcted, the muscle tone of the right side of the limbs may decrease rapidly, and the patient may not be able to move normally, and may even have right hemiplegia. 3. Unconsciousness: left hemispheric infarction also affects the excitability of the cerebral cortex, and the patient may also have the performance of unconsciousness. Left hemispheric infarction may also have headache, dizziness, cognitive impairment and other symptoms, need to be promptly conducted brain CT or MRI to clarify the location of the infarction, and in the later stage, we should adhere to the regular functional exercise and follow the doctor’s instructions to take medication regularly, try to get a better prognosis.