Ramila:

your referees should know about the style of writing them; They might have some samples to mimic some for you;if in a single note u r willing to have this; just sit and make some compliment on yourself, still organizing as above in my previous post

Now, take a look at below:

This is to certify that YOUR NAME completed his undergraduate studies in our MSc degree program in YOUR MAJOR as one of our best students in our program at the Engineering department during his first 2 years of study. I have known him since I was his teacher for some credits. He took his “COURSE 1”, “COURSE 2” , “COURSE 3” and “COURSE 4” with me and his exam results were the top %5 of the class among all students.
After completing his MSc from our department, his results showed that he was among the best students ranked among the other manufacturing students at the time of graduation.
As his competence in English skills is concerned, he has excellent abilities in written and oral English as well as comprehending lectures presented in English.
He has an outstanding potential to deal with research work and surmount its challenging perfectly, making him absolutely qualified in underlined research works and topics. Following his creative personality and sense of introducing novel ideas, He has offered a new method to develop a new device as an abrasion test, which has well been welcomed by our industries.
I believe that your name has ability and enthusiasm to do well in his next research, work and studies at your university; thus, I strongly recommend him for getting an admission to your university as I understand his abilities and academic background which will support him to do his best in his postgraduate study leading to a PhD degree. In addition, he is a very polite, hard working, self-standing, initiative and responsible person. Also, regarding his knowledge, excellent performance and commitments, I believe he is a very suitable candidate
I will be very delighted to inform you more about his activities and personality helping you assess his competence and research quality.

WARNING:
Be careful of only using this as a sample with some keywords and sentences; using the whole body of this letter by a copy paste will provide schools with identical RECs that could be very harmful detrimental!! to your application

I am the source of this letter and using this would be legal;