Table schema:
CREATE TABLE ref_product_categories (product_category_description VARCHAR, product_category_code VARCHAR); CREATE TABLE products (product_category_code VARCHAR, product_description VARCHAR)

Question: Find the category descriptions of the products whose descriptions include letter 't'.
SQL: SELECT T1.product_category_description FROM ref_product_categories AS T1 JOIN products AS T2 ON T1.product_category_code = T2.product_category_code WHERE T2.product_description LIKE '%t%'