Why is my 2nd gear making a very loud clicking/grinding noise?

What is your question?

every other gear seems to be fine, but when i shift into 2nd gear, it jerks when i begin to rev up and also it makes a very loud clicking noise when i go slower, but it turns into more of a grinding noise when i go faster. also, when shifting from reverse it is often hard to get the shift knob back into 1st gear position. any help?