When accelerating with a decent amount of force it sounds like the engine revs up but the car doesn't go quicker, you can see and hear the engine revs increasing but the car doesn't go faster.

Car does not move when clutch engaged

When trying to pull away in the car by engaging the clutch the car doesn't start to move.

Clutch makes strange noise when pressed

When putting your foot on the clutch pedal the car makes a strange mechanical scraping kind of sound. When you take your foot off the clutch the sound stops.

Gear changes are difficult

Changes between gears have become difficult, the gearstick no longer moves freely between gears, it sometimes seems to get stuck or won't go into a gear properly.