Table: gastao_elias_matches
Columns: edition
round
date
against
surface
opponent
w_l
result

Question: WHAT WAS THE SURFACE MADE OF WHEN THE OPPONENT WAS GEORGE KHRIKADZE?
SQL: SELECT "surface" FROM gastao_elias_matches WHERE "opponent" = 'George Khrikadze'

Question: WHAT WERE ALL OF THE RESULTS WHEN THEY PLAYED AGAINST LITHUANIA AND THE SURFACE WAS MADE OF CLAY?
SQL: SELECT "result" FROM gastao_elias_matches WHERE "surface" = 'Clay' AND "against" = 'Lithuania'