(;FF[4]GM[1]SZ[13]ST[2]CA[UTF-8]AP[SGFC:1.17]VW[]

PB[Onur]
BR[16k]
PW[The Many Faces of Go]
WR[15k]
KM[4.5]
DT[2010-06-20]
RE[W+17.5]
RU[Japanese]

;B[cj];W[kc];B[cc];W[kk];B[hc]SQ[hd][jd][fj][hj][jj][ek]C[Is it a good attack to play black 5?

This isn't attack - it's extension. Corners with stone in 3,3 position are very safe, and H11 is too distant to threaten them. What you want at this point is either extending your framework.

H9 is OK move. Extension like H10 or H4 would probably be better, as fourth line stones are more difficult to attack. Or something very safe like E3/F4 from which you'd either take lower side or whole left part of the board depending on white response.

K10/K4 would actually attack white corner, and would be OK too, but they feel rather early for that now.]
;W[fc]SQ[de][he][cf]C[And... what I must do against white 6 to defend correctly?

C11 is much more secure than H11 - the most natural move would be one space jump to H9. An alternative would be building up from C11 to put pressure on the white invading stone with C8/D9 but white is a bit too far, and H11 is a bit too much in danger to be getting into that. H11 is a priority.]
;B[ec]C[If you do that, white will almost invariably respond by extension with F10 or F12 - and this extension will strenghten it.

Before - white F11 is weak. After E11/F12 exchange - white is stronger and H11 is in far more trouble.]
;W[fb];B[fd];W[ed];B[ee];W[ek];B[dk]SQ[gc][dd][gd]C[Is black13 a good defence for the corner?

Looking at corner only it's good. On the other hand top side is very urgent - both F11 or H11 are on verge on death and a move like G11/D10/G10 is worth a lot more than points in corner.]
;W[el];B[dl];W[gd];B[dd];W[gc];B[hd];W[ge];B[ff]SQ[jb][ke][fh]
[ej][jj]C[This move is too slow. If you abandon H11 without getting compensation and settle on a safe border now, you lose on points - and white groups are still weak at this point, but just a few moves away from becoming very strong. Any of the points marked would put more pressure on white, for greater profit.

It's probably the last chance for stirring trouble with H11 group with K12 or L9 or such. E4/K4 will be good big moves for some more time.]
;W[he];B[gf]SQ[fh][gh][ej][jj]C[More fighting spirit! G8 gets you some points but neither strengthens your stones nor threatens white.]
;W[hf];B[gg]TR[fg]SQ[gh][gi][ej][jj]C[There's a saying that open triangles (like F8/G8/G7 with F7 empty) are bad. No matter what situation on board, a shape like that is almost always a bad idea - it is too slow, and a move like G6 or G5 would be twice as powerful (in addition to E4/K4 I mentioned before)]
;W[jf];B[eh]SQ[ej]C[Is it a good defence to play black 27?

It's not good. The correct move would be E4 - white would have to respond and you extend your territory, attack white E3 group, keep your wedge into territory around K4 opened, and get extra defennse for free.

Also - left black side is rather safe and it doesn't need much defense. White invasion would have small chances - the danger is more from white extension like E5 - which you cannot attack from the right without endangering your left side. This argument points to E4 again.]
;W[hj];B[gj];W[gk];B[fj];W[gl];B[em]SQ[eb][hg][hi][ki]C[This is a very bad move. E1/F1/D1 is gote as white is already protected with G2 and it only gets you one point. You essentially throw away the move this way.

Meanwhile - H5/H7 are big open points. Something like L5 is a nice speculative invasion - threatening to either connect or make small life on the side depending on white response. E12 protects against white slide at C13 worth something like 8 points - still less than area on lower right, but much more than E1 and will need to be protected in a few moves.]
;W[fm];B[dm];W[id];B[ej]SQ[eb][hg][hi][ki]C[White was kind enough to throw the move away with J10.

You should take advantage of that and reduce with H5.];W[ik]
;B[hi]C[A bit late. J3 protects white against H5.];W[ii];B[hh]
;W[ih];B[hg]C[This is one point move. E12 is worth a lot more.]
;W[ig];B[eb]C[White let you get away with it by playing J7 instead of C13, but shouldn't.]
;W[fk];B[fa];W[ga];B[ea];W[fe];B[ed];W[jd];B[tt]C[Thanks for your comments :)

Summary: Figuring out which part of the board is most important, and which groups need most attention at the moment would get you most improvement, but it's also very difficult.

Not making empty triangles and one point gote moves is not worth as much, but shouldn't be that hard.]
;W[tt])
