WhiteSmoke Inc. of Boston, designers of "an advanced English language grammar and writing engine," said its recently completed survey of 1,000 users showed that even though nearly half the respondents claim good grammar and spelling were important to them, 85 percent of their documents contained grammar and spelling mistakes.

The company said it conducted the text analysis and research in conjunction with the release of its latest product, WhiteSmoke 2008 Extended Edition. It said the company's team of linguists analyzed 5,000 writing samples.

"The poor quality of writing is troubling," said Amit Greener, the company's vice president of sales and marketing. "However, it is encouraging to know that despite getting basic sentences wrong, the majority of survey participants regard quality writing as important."

The most common errors were omissions of such words as "be," "have," "do," "in," "on" and "at" -- with 27 percent of the surveyed writers forgetting to include the words in simple sentences. Also frequently missing were "a," "an" and "the."