Let the missing terms of the series be x_{1} and x_{2}.

Thus, the sequence 2, 15, 4, 12, 6, 7, x_{1} x_{2} is a combination of two series :

I. 2, 4, 6, x_{1} and II. 15, 12, 7, x_{2}I consists of consecutive even numbers.

So, missing term, x_{1} = 8.

The pattern in II is - 3, - 5,......So, missing term, x_{2} = 7 - 7 = 0.