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

### Instruction:
Ian had twenty roses. He gave six roses to his mother,  nine roses to his grandmother, four roses to his sister, and he kept the rest. How many roses did Ian keep?

### Response:
 อีแอนให้ทั้งหมด 6 + 9 + 4 = <<6+9+4=19>>19 ดอก
ดังนั้น อีแอนเก็บกุหลาบไว้ 20 - 19 = <<20-19=1>>1 ดอก