STDs

Can STDs be spread through Oral Sex? If yes, how? (Would appreciate little Scientific Facts since I have no knowledge about the issue).If the answer to "1" is Yes, do you ACTUALLY have Oral Sex with Condoms to prevent this?Can STDs be spread with Cum Swallowing?Do you enjoy Cum Swallowing?Would appreciate serious answers since some of the questions are Health related. Thx in advance, Friendly Community. Also sorry for my English.