CREATE TABLE table_17513 ("Chapter" FLOAT, "Chinese" TEXT, "Pinyin" TEXT, "Translation" TEXT, "Subject" TEXT)

How many subjects have the pinyin shixun?
SELECT COUNT("Subject") FROM table_17513 WHERE "Pinyin" = 'Shixun'
SELECT COUNT("Subject") FROM "table_17513" WHERE "Pinyin" = 'Shixun'