给出一篇英语文章，计算其中每个单词的出现次数。


"A fox saw the dog and jumped over it. The dog didn't notice the fox."
Here are the word frequency counts for the given passage:
- a: 2
- fox: 2
- saw: 1
- the: 3
- dog: 2
- and: 1
- jumped: 1
- over: 1
- it: 1
- didn't: 1
- notice: 1