Question: How many times on page number 16 does the second word in the pair of words 1 and 109 appear?
SQL: SELECT SUM(T1.occurrences) FROM pages_words AS T1 INNER JOIN biwords AS T2 ON T2.w2nd = T1.wid WHERE T2.w2nd = 109 AND T2.w1st = 1 AND T1.pid = 16