History of violence
Very rarely is abuse or violence a one-off event: a batterer will beat any person they are with; a sexually abusive person will be abusive toward all their intimate partners.
Sometimes the abuser may tell you himself/herself that he/she has hit or sexually assaulted someone in the past. However, they may then not take responsibility and shift the blame on to the victim.
They may tell you that it won't happen with you because "you love them enough to prevent it" or "you won't be stupid enough to wind me up that much". Once again, this is denying their own responsibility for the abuse, and shifting the responsibility for the relationship to remain abuse-free on to you.
Past violence is one of the strongest pointers that abuse will occur.
Using force during an argument
This is a big warning sign. What starts off in early courtship as a bit of a push or a shove, can turn into full-blown beatings not long down the road. An abuser may physically restrain you from leaving the room, lash out at you with his/her hand or another object, pin you against a wall or shout 'right in your face'.
Any form of force used during an argument can be a sign that serious physical violence is a strong possibility.
Breaking or striking objects
An abuser may break your treasured object, beat his/her fists on the table or chair or throw something at or past you. Breaking your things is often used as a punishment for some imagined misdeed on your part. Sometimes it will be justified by saying that now that you are with him/her, you don't need these items any more.
Breaking your possessions also has the effect of de-personalising you, denying you your individuality or literally trying to break links to your past. Beating items of furniture or throwing objects will often be justified by saying you wound him/her up so much they lost control, once again shifting the blame for this behaviour on to you, but is actually used to terrorise you into submission.
Only very immature or abusive people beat on objects in the presence of other people in order to threaten or intimidate them.
This would obviously include any threat of physical force such as "If you speak to him/her again, I'll kill you", or "If any wife of mine acted like John's did, I'd give her a right seeing to".
Threats are designed to manipulate and control you, to keep you in your place and prevent you making your own decisions. Abusers may tell you you're "over-sensitive" for being upset by such threats, or obviously want to hurt him/her.
Threats can also be less overt, such as "If you leave me, I will kill myself", or "You are so wonderful, I will never let you go/couldn't live without you".