Because it has something covering it and he has to watch his back
Depends on how major or minor the errors are. If the errors are due to lack of knowledge then it isn't a sign of progress but if less errors are being made and they are small ones progress may be shown.
Makes notes! And communicate with your teachers, standing up for yourself and asking for what you need can get you far
Lurks/B is the correct answer due to the plural and just proper English/grammar.if you were to use the term “Lurk” it wouldn’t make sense so the proper English would be “Buried deep under a pile of rocks LURKS a cunning predato”.