Cue after stimulus onset

Hello,

In the experiment I am trying to program, on each trial there is a cue (#) and a stimulus (a word which the subject has to read out loud). In some trials, the cue precedes the word - there is no problem with these trials. However, in other trials, the cue should appear after the word is already on the screen: I want the word to appear first, then 50ms later the cue should appear and stay on the screen (together with the word) for 50ms, and finally the participant should record his or her response.
I tried to put both the word and the cue one after another in the same trial (as I did for the pre-cue trials), but this way the program waits for response for the word and only then proceeds to presenting the cue. What I would like to do is to allow for the word to stay there and collect the response only after the cue has already disappeared.
Is this possible? If so, how can it be done?

Many thanks (:
Neta.