How many events did the 88-years-old male users participate on 4th May,2016?
88-years-old refers to age = 88; male refers to gender = 'M'; on 4th May, 2016 refers to timestamp LIKE '2016-05-04%';
SELECT COUNT(T2.event_id) FROM gender_age AS T1 INNER JOIN events AS T2 ON T2.device_id = T1.device_id WHERE T1.gender = 'M' AND SUBSTR(`timestamp`, 1, 10) = '2016-05-04' AND T1.age = 88