Diagram 1, Black invades move-1 is a common tactic, White has three options from A, B to C.
Diagram 2, White squeeze move-2 is a common answer shown on study book. Black move-3 is a trick move and if White fell for it, the result is disastrous for White.
Diagram 3, Thus, White correct answer is at move-1 because Black move-3 from Diagram 2 is a wrong move. Now Black has to sacrifice his stone.
Diagram 4, Black move-1 here is proper move. White is forced to give up the corner stone and ends in gote.
Diagram 5, If White chose to hane at second-row move-2, Black can easily acquire influence outside. White is not happy.
Diagram 6, Black cross-cut at move-1 is very popular move due to conditional-met. If White chose to defend at move-2, the result is too happy for Black because White is not settled.
Diagram 7, To reply move from Diagram 6 -White replies atari move-4. Notice that the result is bit similar with Diagram 4 but Black obviously not happy because of gote.
Diagram 8, If White chose to give up the corner stone by answering move-4 to counter Diagram 5. White cannot be too happy because potential aji stone.
Diagram 9, After all above answers by White, Xinwen has suggested White hane at move-1 seem to be the best answer.
Diagram 10, Black extends move-3 and capture White’s stone at move-7 resulted too good for Black. If White continues at A trying to live..
Diagram 11, Black can poke at move-6 and White ended with just one-eye or KO to live. So how must White answers?
Diagram 12, White atari sacrifice at move-6 is the correct answer.
Diagram 13, after sacrificing move-6, White solidifies itself at move-10.
Diagram 14, If Black extend at move-11, Black is very unhappy to be ended in gote to make living at A.
Diagram 15, Black’s correct answer is at kosumi move-1 shown in this Diagram. The result is considered to be even provided White has thickness and Black has sente.
Lastly, Xinwen hopes the reader can learn and benefit from this lecture.