Ever wanted to get inside the mind of the opposite sex? Ever wonder exactly what attracts men and women? A new survey by MarketTools Inc. for the dating website Match.com offers some answers.

The survey asked 5,500 unattached adults 21 and older what qualities they judge most in the opposite sex. The survey also asked singles to rate their "must haves" when it comes to relationships.

The survey said 48 percent of single women and 38 percent of single men research a date on Facebook, and 38 percent of singles said they would cancel a date because of something they found about the person on the Internet. Forty-two percent of singles would not date a virgin and 49 percent would get into a committed relationship with someone who still lived with their parents.

Check out the findings below:

Ten things on which men judge women most:

1. Teeth-58 percent.

2. Grammar-55 percent.

3. Hair-51 percent.

4. Clothes-45 percent.

5. Having/not having a tattoo-40 percent.

6. Nails/hands-37 percent.

7. Accent-19 percent.

8. Shoes-18 percent.

9. The car they drive-13 percent.

10. Electronic devices they carry-9 percent.

Ten things on which women judge men most:

1. Teeth-71 percent.

2. Grammar-69 percent.

3. Clothes-58 percent.

4. Hair-53 percent.

5. Nails/hands-52 percent.

6. Having/not having a tattoo-34 percent.

7. Shoes-29 percent.

8. The car they drive-24 percent.

9. Accent-22 percent.

10. Electronic devices they carry-10 percent.

Men's top "must haves" in a relationship:

The person is someone I can trust and confide in-63 percent. Treats me with respect-57 percent. Is physically attractive to me-40 percent. Has a sense of humor/makes me laugh-37 percent. Is comfortable with her own sexuality-36 percent.

Women's top "must haves" in a relationship:

Treats me with respect-84 percent. The person is someone I can trust and confide in-77 percent. Has a sense of humor/makes me laugh-58 percent. Shares the same values as I do-47 percent. Is comfortable communicating his wants, needs and desires-46 percent.