Abusive behaviours have become normalised for young people in relationships, a new survey has found.
A relationship quiz from Women's Aid, taken almost 20,000 times online, revealed that 93% of young people said their partner has threatened to post explicit images or videos online when they have a fight.
Some 83% said their partner has hit them once and they are afraid they will do it again.
Meanwhile 72% said the person they are going out with always demands to look through their phone and to know all their passwords.
And 69% said their partner has forced or pressured them to do something sexual that they did not want to do.
Mary Hayes leads the #TooIntoYou campaign.
She said for many young people, the red flags of abuse can be difficult to spot.
"We have seen some really shocking trends coming through in the TooIntoYou relationship quiz," she said.
"A common, unhealthy behaviour we hear about from young people is when their partner demands to look through their phone and social media to see who they’ve been talking to.
"This is really worrying because it is an indication that their partner is trying to control who they talk to and doesn’t respect their privacy.
"Your partner demanding to look through your phone and knowing all your passwords is a common red flag of abuse.
"In young relationships it can be confusing because if this is seen as the norm, it sets a precedent for other unhealthy behaviours which can get worse and more dangerous over time".
'A harmful picture'
Ms Hayes said abusive behaviours must be called out.
"If those behaviours continue to be brushed off as 'not a big deal,' or excused as jealousy or insecurity, then it creates a harmful picture of what young people should expect in their intimate relationships," she said.
"It is essential that we call these behaviours out as abusive and unacceptable.
"So much of what young people understand about relationships is unhealthy.
"We want young people to know what an unhealthy relationship looks like, so they are able to spot the red flags early on before things get more serious and they become isolated," she added.
Anyone affected by issues raised in this article can contact the Women’s Aid 24hr National Freephone Helpline on 1800-341-900