Can a self-paced-reading & grammaticality judgment task be programmed in PsychPy or Open Sesame? I want to know if it is possible to design an experiment on PsychoPy or Open Sesame in which the subject does a self-paced reading (with measuring the reading times for each word), and then after they've read the last word, they judge whether the sentence is grammatical or not (also need RT measured from the end of reading the sentence until responding to the grammaticality question).

I'm not familiar with the two programs, but I plan on learning (I played with PsychPy for a mini-experiment). I want to know whether I'll be able to do such an experiment with either of these of these programs before going any further in my methodology.
Disclaimer - I'm a big fan of, and occasional contributor to, OpenSesame. 


Yes, but you can't expect anyone here to do it for you. 
I would recommend using OpenSesame for this, as you'll need to use Python, and OpenSesame makes this side of things easier for beginners. 
My advice is to head over to the website, take a look at the documentation there, have a go yourself, and use the forum there to ask for help in specific points.

I will say though, that it's much better to attempt to design the experiment yourself and ask for help, rather than looking for someone to do it for you. The OpenSesame people really appreciate that!