A std may be compared to some percent of teens.Logical formLearned from2 sentences. Some percent of some American girls may be infected with a std.Logical formLearned from2 sentences. (Health effects) of stds can be severe.Logical formLearned from2 sentences. Some sites may receive details of admissions from (government std clinics).Logical formLearned from2 sentences. A person may go to (std clinics).Logical formLearned from2 sentences. (Std rates) can be in a country.Logical formLearned from2 sentences. (Std rates) may remain high.Logical formLearned from2 sentences. Concern can be about stds.Logical formLearned from2 sentences. Folks may contract stds.Logical formLearned from1 sentences. Stds can be among teen-agers.Logical formLearned from1 sentences. (Epidemic rates) can be constituted-of-or-filled-with stds.Logical formLearned from1 sentences. A possibility of stds can be real.Logical formLearned from1 sentences. Persons may learn from stds.Logical formLearned from1 sentences. Stds may be diagnosed among teen-agers.Logical formLearned from1 sentences. Some form can be constituted-of-or-filled-with std.Logical formLearned from1 sentences.