Who of the consultant is not certified, show their names and id.

The easy solution would be to do these for you but aside from making my eyes bleed these look like simple join queries to me.

May I suggest you learn a bit about the join syntax in T-SQL through this great article here. Once you understand it a bit better you might be able to see how these queries and others you posted on here can be answered.

This could be more valuable in terms of personal development than just getting the answer.

You have provided nothing more than a query. You need to provide some detail and what your actual question is.

Michael, use INNER JOIN and here is the general syntax

SELECT column_name(s)
FROM table_name1
INNER JOIN table_name2
ON table_name1.column_name=table_name2.column_name

So based on the above syntax; for your specific question try something like this..

Select CONSULTANT.C_id, CONSULTANT.C_last, CONSULTANT.C.First
From CONSULTANT 
     INNER JOIN CONSULTANTS_SKILL 
     ON CONSULTANT.C_id = CONSULTANTS_SKILL.C_id

Good Luck!