Most students think a recommendation letter is binary: the teacher said yes, so the letter is good. It is not. Letters are coded. Two letters that look the same to the writer can read very differently to a trained admissions reader. Here are the phrases admissions officers tell us they actually look for.
Three phrases that mean a yes
"One of the top X students I have taught in Y years."
This is the gold standard. The number matters. "Top 3 in 22 years of teaching" lands very differently than "top student this year." Readers especially weight this when the teacher has been teaching for a long time and has a reputation for being a hard grader. If your teacher writes this, the letter is doing real work.
"I would hire her tomorrow / I would want her in my graduate program."
Specific projection into the future. The teacher is not just praising your past — they are betting on you. Variants: "I expect to be reading about her work in ten years," "He is the kind of student who changes a department," "She will thrive at any institution that admits her." These are signals that the writer has stopped writing a generic letter and started advocating.
A specific anecdote with names and dates
Strong letters contain at least one specific story. "During the unit on Reconstruction, Maya raised an objection to the textbook's framing that I have been thinking about ever since" is worth more than three paragraphs of "insightful, thoughtful, mature." Specificity in a rec letter signals that the teacher actually knows you. Generic praise signals they do not.
Three phrases that mean a no — or worse, indifference
"He was always polite and prepared."
This is a damning sentence in a rec letter. It is what teachers write when they have nothing else to say. Readers translate it as: "This student showed up, did the work, and did not stand out." That is the kiss of death at a T20.
"She is one of the top students in my class this year."
Notice the difference from the gold-standard phrase: "this year," no number, no comparative range. Readers read this as "she is in the top half of one section of one class." That is not enough.
Praise that could apply to anyone
"Diligent. Hardworking. Curious. A pleasure to have in class." Every one of these adjectives appears in roughly 80% of rec letters. They are not negative — they just do not move the rating. A letter built entirely from these adjectives is, functionally, a no.
How to actually get a strong letter
The teacher writes the letter, but you set them up. Here is what works:
- Ask juniors-year teachers from courses you visibly engaged with — not necessarily the courses where you got an A.
- Ask in May or June of junior year, not September of senior year. Strong letters take time. Late asks get formula letters.
- Send a brag sheet. One page. Your goals, three specific moments from their class you are proud of, the kind of programs you are applying to, and a deadline reminder.
- Pick two teachers from different subjects (one STEM, one humanities) unless you are applying to a specialized program.
- Follow up with a thank-you note in October. Not strategic — just decent.
What to do if you suspect your letter is weak
You will never see your letter — that is on purpose. But you can read the temperature. If a teacher hesitates when you ask, asks you to write a draft for them, or says "I will see what I can do," the letter will be polite at best. Politely withdraw the request and ask someone else. It is awkward for one minute. The alternative is a flat letter sitting in your file for the next four months.