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

### Instruction:
 Ed和Jacob的贝壳收藏已经有2个贝壳了。然后他们去海滩收集更多贝壳。Ed找到了7个帽螺贝壳，2个牡蛎贝壳和4个海螺贝壳。Jacob比Ed多找到了2个贝壳。这对夫妇总共有多少贝壳？


### Response:
 Ed在海滩上找到了7个贝壳 + 2个贝壳 + 4个贝壳 = <<7+2+4=13>>13个贝壳。
Jacob在海滩上找到了13个贝壳 + 2个贝壳 = <<13+2=15>>15个贝壳。
总共Ed和Jacob有2个贝壳 + 13个贝壳 + 15个贝壳 = <<2+13+15=30>>30个贝壳。