As Sean has said it would be much easier to provide a workable answer with additional information.

Here's an idea on how to do it (I have no way of knowing how to join the tables):

SELECT

DATENAME(MONTH, T.theDate) AS theMonth,

SUM(T.value) AS value1,

SUM(T1.value) AS value2,

SUM(T2.value) AS value3

FROM

dbo.test AS T

JOIN dbo.test1 AS T1

ON T.primarykey = T1.foreignkeytoT

JOIN dbo.test2

ON T.primarykey = T2.foreignkeytoT

GROUP BY

DATENAME(MONTH, T.theDate)