The characters like Mrs. Thomas Fedler, Mr. Gribly, Miss Turner, and sam Gribly
Alter means to change or make a slight change. so natural forces like mud or rain can shape what the earth looks like and what it does.
It's important for readers to understand how is because, when you write a story, or a school report, if you don't make some sort of suspense, people are going to get bored, or lost. Readers also should know why writers create suspense because, it's always a good idea sometimes, to stop yourself, and say, "Why did this happen"? Asking why helps you to understand, and visualize what's going on in the peice of writing.
That's all I got. Hope this helped!!