Great, how many males friends does she have?
SELECT count ( * )  FROM Person AS T1 JOIN PersonFriend AS T2 ON T1.name   =   T2.friend WHERE T2.name   =   'Alice' AND T1.gender   =   'male'
count of male friends = count(*) WHERE gender = 'male'; she refers to a specific person's name, in this case 'Alice'; friends refers to the relationship defined in PersonFriend table;