求几篇申请出国读研的英文推荐信的范文，感谢各位大神

To Whom It May Concern:
As Principal of George Mason High School I am delighted to recommend to you a stellar member of our teaching staff, Mr. Samuel Cohen, and to write this letter on his behalf. Sam has taught American History at the school for three years. He is one of our most popular and effective instructors and has already won several teaching awards.
He came to us directly upon completion of his bachelor’s degree, but immediately settled in as if an old pro. Sam is a master of all of the ingredients of successful teaching, especially the ability to inspire.
This gentleman is highly professional in both dress and demeanor. To my knowledge Sam has never come to work without both a suit and tie, more times than not a bow tie. The majority of others at the school, both teachers and students, dress differently and lean to more informality. Never once, however, has Sam’s manner of dress elicited the slightest comment. Why? It is simply because Sam’s attire seems entirely natural given his dignified comportment.
That comportment in turn is driven by Sam’s love and respect for American History. Sam views himself as the messenger for something serious and important, and this is reflected in the way he teaches and in the way his students respond.
Reaction to Sam’s classes has been overwhelmingly positive. So much so that more than once it has been reported to me that study hall students have been spotted lingering outside the door to Sam’s classroom listening to his lessons.
Sam’s impact has even been felt outside the school with the parents themselves. His section on the importance of voting has inspired students to cajole their parents to register to vote. Several have mentioned this to me at parent-teacher meetings. One even called the school to have me pass on their thanks to Mr. Cohen.
The only thing that we in the school administration have ever worried about in regard to Sam is the prospect of funding his bottled water. Sam is such a passionate and prolific speaker that he needs a steady supply to maintain his voice. So far we have gotten a pass on this, as students have bought it for him, including what must have been a year’s supply on his last birthday.
It will be a sad day when we announce that Sam will be pursuing his graduate degree on a fulltime basis. We can only hope that he keeps his promise and returns to us as soon as the ink is dry on his new diploma.
Sincerely,
Harold W. Brown
Principal
George Mason High School