promise and face questions of principle

Promise = const new new Promise ((Resolve, Reject) => { 
    the console.log ( . 1 ); 
    Resolve (); 
    the console.log ( 2 ); 
}) 
promise.then (() => { 
    the console.log ( . 3 ); 
}) 
the console.log ( . 4); 
the above output result 1243 
is first performed immediately after the new Promise, it will first output 1, while Promise.then () internal code when executed immediately at the end of the event cycle times, it will be first output 4, the final output 3.