What can I do to fix my Macbook Air 2011—it is no longer letting me highlight, or click on things
If the trackpad is not physically broken, it is most likely that the batteries have started to swell (as they usually do in older computers). You should probably go to the nearest Apple Store and have your computer looked at. If it is not taken care of, the batteries will expand enough to damage the case of the computer (see below) and possibly become an explosion hazard.