Cant change gear and now power

My wife drives a Hyundai Tucson and has had it from new. Never had a problem with it until this year. Now when driving we have an intermittent problem of no power that feels like the clutch is slipping and that you can´t change gear. Had it checked by the local garage and now clutch problems. They are as stumped as us now as to what to do.
I dare not let the wife out driving in it as the last time she was stuck on a back road not being able to change gear on bends or able to change down to pull away again.