Here are the suggested words to fill in the blanks:

1. **home**
2. **were planted**
3. **natural habitat**
4. **I’d seen**
5. **amazed at**

So the completed passage would read:

"Last year, I visited the Somerset Levels, a coastal plain and wetland area in Somerset, South West England. This area is (1) **home** to one of Somerset’s oldest traditional crafts - willow basket making. Basket making began in the area a long time ago. At the beginning of the 19th century, more than three thousand acres of willow trees (2) **were planted** commercially there because the area provided an excellent (3) **natural habitat** for their cultivation. (4) **I’d seen** willow baskets before I visited the Levels, but I was still (5) **amazed at** the numerous products created by the basket makers there."