Respuesta :
1. They might be using the wrong kind of soil for the plants, causing them to die.
2. The new neighbors could be adding something toxic to Bill's grandparents' plants.
3. Maybe what the neighbors are adding to their garden is affecting Bill's grandparents' garden on the other side of the fence.
The things that are causing Bill’s grandparents’ garden to die off include microbe and new plant species by the neighbor.
There may be microbes in the rainwater that was collected. In this case, the microbes could have infected the plants and thus will have affected the growth of the plants.
Also, the new neighbors may have brought in new plant species and this may have had adverse effects on the plant. In such a case, it may have led to the death of the plants.
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