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

### Instruction:
 伊恩有二十朵玫瑰花。他给了他妈妈六朵玫瑰花，给了他奶奶九朵玫瑰花，给了他妹妹四朵玫瑰花，剩下的他自己留着。伊恩留下了多少朵玫瑰花？


### Response:
 伊恩总共给了19朵玫瑰花，即6 + 9 + 4 = <<6+9+4=19>>19。
因此，伊恩留下了20 - 19 = <<20-19=1>>1朵玫瑰花。