I always liked to return a back-hand smash with another back-hand left twist counter!

what you allow your mind to be exposed to, determines how you concentrate. one must become "quiet" in your mind to "focus' on your concentration. one way to "quiet" your mind is to find peace with who you are at this very moment, not looking outward but looking inward for peaceful relaxing well being thoughts about yourself sometimes just repeating "all is well, all is well' until you feel all really is well. getting the proper sleep and eating habits affect all of us as well. The creator of this Universe knows what you
need and supplies those needs when asked, Improve your concentration by eliminating all conflicting distractions, try relaxing and counting backwards from 100 and when you get to "5", say to yourself " I will always maintain a single concentration in my mind "AND REPEAT THAT UNTIL YOU COUNT DOWN TO "1"

being jealous is a "self" induced action, it's purpose is to alienate you from something or someone. where there is "unconditional"
Love, there brings no thought contrary to it, so love without conditional requirements from inside yourself and you will be free to be "me" !

on April 11th,2014, my wife suffered a diabetic stroke, which took her sight and put her in a wheel chair, although she is improving all the time, i , became the cook she needs to satisfy her dietary requirements, previously my wife taught me cooking and now i enjoy doing the cooking for us. i am 74 yrs old and she is 70. it is never to late to learn new things... hope this helps some one else!