The lengths of the morse code elements are approximately defined with the length of the dot. Dash is three times as long as a dot.
Spaces between letter elements are "dot-long", spaces between letters are dash-long. You simply make a little bit wider space between words and a minus (-...-) between statements.
Besides morse code itself I find very amusing a whole lot of abbreviations and acronyms. It is tedious to transmit and receive long words of human language so we rather TX ES RX (transmit and receive). There are written and unwritten codexes for these. Some of them are standardized like Q-codes (used widely in marine, aviation, ham and other communications), international standard abbreviations (a thick book which was used in marine communications and enabled two people to communicate without knowing each other's language), others are not (hamradio, CB, ...).
VY 73 ES GD DE S57BDX SK E E