Developed Is Not Active: Piece Activity vs Development

Good day, chess world!

This is the tenth game in Capablanca's own Chess Fundamentals.
Capablanca shows something very important about exiting the opening. Development just means your pieces are off the back rank, activity means they actually do something.
Playing White against Frank Marshall.Capablanca gets his pieces working while Marshall's merely stand developed. This turns into the decisive point of the game.

If you are enjoying my posts takes a look at the lesson link below on my website for further lessons and consider signing up for the free daily lessons with the links below.

Four exercises from the game

Try to solve each before you watch. Capablanca is White here and wins, so every exercise asks for White's move, the choice that turns development into real activity. The answers are in the full game at the bottom, in the video, and in the website lesson linked below.

Exercise 1. White to play (move 12). Everything is nearly developed. Which bishop move makes the pieces active and points the whole force at the black king?

Exercise 2. White to play (move 14). Which capture snatches a pawn safely, because Black's developed pieces cannot punish it?

Exercise 3. White to play (move 18). Which knight jump into the centre wins material by force?

Exercise 4. White to play (move 34). Which capture liquidates into a trivially winning rook ending?

Play through the full game with my notes here:

Questions, or a move you would have played differently? Tell me in the comments. Good day, chess world.

Watch the video and go deeper

https://www.youtube.com/watch?v=p576FtA4pjM

Free interactive lesson for this game, with board diagrams and six puzzles, on my website: https://chessexcellence.com/f/chess-piece-activity-vs-development-capablanca-marshall-1914.html

Free Capablanca notes (PDF): https://docs.google.com/forms/d/e/1FAIpQLSfVtlFBDTaYahWI-VcpZOUIGn7ly5R4mYnjoEgg2OOgHn1tzQ/viewform

Free study sheets from my Logical Chess Move by Move series: https://forms.gle/nEt1DWY5pKGq7T3n6

See the whole Capablanca's Chess Fundamentals series: https://www.youtube.com/playlist?list=PLYil0efSf2As