Below is an instruction that describes a task. Write a response that appropriately completes the request in Chinese. Please answer in Chinese.

### Instruction:
 查尔斯买了20张纸来画画。今天，查尔斯画了6幅画。昨天他上班前画了6幅画，回来后又画了一些画。知道他还剩2张纸，那么查尔斯回来后画了多少幅画？


### Response:
 查尔斯画了6 + 6 = <<6+6=12>>12幅画。
他还剩20 - 12 = <<20-12=8>>8张纸。
所以查尔斯回来后画了8 - 2 = <<8-2=6>>6幅画。