Q: Won't grab a gear

It sounds like you are saying that while the engine is running, you can actually disengage the clutch such that you can switch gears, but there is no engagement upon release of the clutch . If there is a visible "linkage" (lever or arm) on top of the transmission which actuates the clutch, look and see if that linkage is actually moving when an assistant depresses (and releases) the clutch pedal. If the linkage is moving (of course you have to guess if you are getting the "right" extent of movement) but you are still not getting any engagement or release of the clutch, obviously the clutch mechanism has failed. As you probably know, in that event, the transmission will have to be dropped in order to do the repairs. By the way, if you are checking the linkage while the car is running be sure NOT to stand in front of the car, do block the wheels, and set the brake in case the clutch suddenly "repairs" itself and the car takes off. In other words, be careful. If you need help having this checked, an expert from YourMechanic can come to your home or office to perform a diagnosis and advise you on repairs.