1 Thessalonians 4:2-5 (KJV)
For ye know what commandments we gave you by the Lord Jesus. For this is the will of God, [even] your sanctification, that ye should abstain from fornication: That every one of you should know how to possess his vessel in sanctification and honour; Not in the lust of concupiscence, even as the Gentiles which know not God:
Hebrews 13:4 (KJV)
Marriage [is] honourable in all, and the bed undefiled: but whoremongers and adulterers God will judge.
1 Corinthians 6:18 (KJV)
Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body.
This one to me is the reason why sexually transmitted disease is so widespread!
2 Timothy 2:22 (KJV)
Flee also youthful lusts: but follow righteousness, faith, charity, peace, with them that call on the Lord out of a pure heart.
Colossians 3:5-7 (KJV)
Mortify therefore your members which are upon the earth; fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness, which is idolatry: For which things' sake the wrath of God cometh on the children of disobedience: In the which ye also walked some time, when ye lived in them.
Galatians 5:19-21 (KJV)
Now the works of the flesh are manifest, which are [these]; Adultery, fornication, uncleanness, lasciviousness, Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies, Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told [you] in time past, that they which do such things shall not inherit the kingdom of God.
Fornication: Sexual intercourse between partners who are not married to each other.
There's more, but if you can't teach her with these, she doesn't want to listen and will suffer for it.
Proverbs 19:29 (KJV)
Judgments are prepared for scorners, and stripes for the back of fools.
This verse means that fools only learn through the consequences of their actions.