(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PW[White]PB[Black]
AW[db][lb][pb][qb][rb][bc][cc][lc][oc][dd][od][pd][qd][be][de][le][re][af][df][mf][nf][dg][pg][qg][bh][dh][nh][oh][ci][bj][bm][cm][dm][dn][do][bp][dp][ep][bq][fq][oq][pq][qq][rq][cr][fr][nr][qr][sr][cs][qs]
AB[cb][nb][ob][nc][pc][qc][rc][bd][cd][nd][ce][ne][oe][cf][pf][ag][bg][cg][og][ph][qh][cn][ao][bo][co][cp][mp][np][op][pp][qp][rp][sp][cq][dq][eq][jq][lq][sq][kr][or][rr][es][rs]
LB[ef:D][lh:A][fn:C][ln:B]
C[4 more problems to test you. In each case black to play. With A,C,D to save some stones and in B to kill; remember no ko's 

A and B are fairly easy, C and D a little more tricky. 

The theme running through all 4 problems is to use  the "dead" stones to save or kill the groups. 


Hints - 
A  shortage of liberties can get you out of a fix 
B  shortage of liberties helps you to crack a hard nut.
C  Keep calm and if you understand the importance of how to use the E1 stone your problem is solved.
D  If you haven't used the C18 stone you haven't solved the problem! ]
)
