Probably. Depositions are where a witness or expert or accused is asked questions about the case way before the trial. That way the attorneys have a record of what you said prior to asking you about it in court.
Also if you're involved in a case that required a police report, you're generally asked what happened and its written in there usually a short period of time (minutes or hours) after the "whatever" occurred.
Not being able to remember is ok too, so long as you say it before you go to court. A witness that can't remember Monday on Wednesday is not a good witness to call before a courtroom and is unlikely to be called.
I saw a guy steal a car once, but I couldn't remember his face. It was early in the morning, dark and the guy had a jacket and hat on. So the police and the attorney elected to not even officially interview me.
Attorneys very rarely ask questions that they don't already know the answer to or at least have a very good idea of what the answer will be.