by Katharine Hansen, Ph.D.

Your cover letter shows employers how well you express yourself. It can also demonstrate that you are savvy in the ways of marketing yourself and selling your best qualifications. A good cover letter can entice the recipient to review your resume. A bad cover letter, on the other hand, can nip your chances in the bud. Here are 10 mistakes that contribute to bad cover letters. To ensure that your cover letter is effective, avoid these mistakes:

1. Sending your resume without a cover letter. Sure, there are some employers that don't read them or place much importance on them. But since you don't know whether the employer you're writing to reads and values cover letters or not, you must include a letter.

2. Failing to address the letter to the specific name of the recipient. Addressing the letter to "Dear Personnel Director/HR Director," "To Whom It May Concern," "Dear Sir or Madam" (or worse, "Dear Sirs") instead of a named individual are all lazy approaches that show the employer that you were not concerned enough to find out the name of the person with the hiring power. It's not always easy to find the name of the specific hiring manager, but try to do so if at all possible. Usually, you can just call the company and ask who the hiring manager is for a given position. Tap into your personal network to learn the names of hiring managers. Let's say a company post an opening online. You know someone who works at the company. Ask your contact to find out the name of the person hiring for that position. Also use the library, phone book, and Internet to track down names of hiring managers.

The worst-case scenario is that your letter will begin "Dear Hiring Manager for [name of position]:" It's not the best approach, but if you absolutely cannot find a name, this salutation does at least provide some specificity.

3. Telling the employer what the company can do for you instead of what you can do for the company. This mistake is particularly common among new college graduates and other inexperienced job-seekers. In most cases, employers are in business to make a profit. They want to know what you can do for their bottom line, not what they can do to fulfill your career dreams. Tell the employer how you can meet his or her needs and contribute to the company.

4. Leaving the ball in the employer's court. Too many cover letters end with a line like this: "I look forward to hearing from you." Proactive cover letters, in which the job-seeker requests an interview and promises to follow up with a phone call, are far more effective. Don't be vague about your desire to be interviewed. Come right out and ask for an interview. Then, take your specific action a step farther and tell the recipient that you will contact him or her in a specified period of time to arrange an interview appointment. Obviously, if you say you will follow up, you have to do so. If you take this proactive approach and follow up, you will be much more likely to get interviews than if you did not follow up. This follow-up aspect is another good reason to obtain the specific name of the hiring manager. Here's a sample closing paragraph requesting specific action and describing the writer's planned follow-up.

I would like to be considered for a sales position in which someone of my background could make a contribution. I will contact you soon to arrange for an interview. Should you require any additional information, I can be contacted at the phone numbers listed above.

5. Being boring and formulaic. Don't waste your first paragraph by writing a boring introduction. Use the first paragraph to grab the employer's attention. Tell the employer why you are writing and summarize the reasons you are qualified for the position, expanding on your qualifications in later paragraphs. Read more. Don't use such cliches as "Enclosed please find my resume" or "As you can see on my resume enclosed herewith." Employers can see that your resume is enclosed; they don't need you to tell them. Such trite phrases just waste precious space. Write a letter that will make the employer want to get to know you better.

6. Allowing typos, misspellings, or incorrect grammar/punctuation into your letter. Your letter reflects your ability to write and communicate. Be sure your document is letter-perfect before sending it out. Proofread your letter. Put it down and proof it again a few hours later with a fresh eye. Then enlist a friend to review it for errors.

7. Rehashing your resume. You can use your cover letter to highlight the aspects of your resume that are relevant to the position, but you're wasting precious space -- and the potential employer's time -- if you simply repeat your resume.

8. Failing to specifically tailor your letter to the job you're applying for. If you're answering an ad or online job posting, the specifics of your cover letter should be tied as closely as possible to the actual wording of the ad you're responding to. In his book, Don't Send a Resume, Jeffrey Fox calls the best letters written in response to want ads "Boomerang letters" because they "fly the want ad words -- the copy -- back to the writer of the ad." In employing what Fox calls "a compelling sales technique," he advises letter writers to: "Flatter the person who wrote the ad with your response letter. Echo the author's words and intent. Your letter should be a mirror of the ad." Fox notes that when the recipient reads such a letter, the thought process will be: "This person seems to fit the description. This person gets it."

A particularly effective way to deploy the specifics of a want ad to your advantage is to use a two-column format in which you quote in the left-hand column specific qualifications that come right from the employer's want ad and in the right-hand column, your attributes that meet those qualifications. The two-column format is extremely effective when you possess all the qualifications for a job, but it can even sell you when you are lacking one or more qualification. The format so clearly demonstrates that you are qualified in so many areas that the employer may overlook the areas in which you lack the exact qualifications. See a sample letter in a two-column format.

9. Rambling on too long and telling the story of your life/career. Keep you letter as brief as possible. Never, never more than one page. Keeping to four or five paragraphs of no more than three sentences each is a good guideline. Using bullet points in the letter is a good way to break up blocks of text and interest the reader. Some job-seekers tend to use their cover letters to provide a narrative of their life or career. That's not what the letter is all about; it's a marketing tool that should focus on the qualifications that will sell you to the employer. Your letter should answer the question that the employer will be asking while reading the words you've written: "Why should I hire this person?" Answer with your Unique Selling Proposition. Use simple language and uncomplicated sentence structure. Ruthlessly eliminate all unnecessary words.

10. Using wimpy language. Avoid such phrases as "I feel" and "I believe." Your statements will be much stronger without them. It's best to either leave off the qualifier or use a stronger qualifier, such as "I am confident," I am convinced," or "I am positive." Read more.

Questions about some of the terminology used in this article? Get more information (definitions and links) on key college, career, and job-search terms by going to our Job-Seeker's Glossary of Job-Hunting Terms.

Katharine Hansen, Ph.D., creative director and associate publisher of Quintessential Careers, is an educator, author, and blogger who provides content for Quintessential Careers, edits QuintZine, an electronic newsletter for jobseekers, and blogs about storytelling in the job search at A Storied Career. Katharine, who earned her PhD in organizational behavior from Union Institute & University, Cincinnati, OH, is author of Dynamic Cover Letters for New Graduates and A Foot in the Door: Networking Your Way into the Hidden Job Market (both published by Ten Speed Press), as well as Top Notch Executive Resumes (Career Press); and with Randall S. Hansen, Ph.D., Dynamic Cover Letters, Write Your Way to a Higher GPA (Ten Speed), and The Complete Idiot's Guide to Study Skills (Alpha). Visit her personal Website or reach her by e-mail at kathy(at)quintcareers.com.

Go back to the Cover Letter Resources for Job-Seekers section of Quintessential Careers, where you will find a collection of the best cover letter tools and resources, including articles, tutorials, and more.