Many parents are always ________ their kids ________ others’.

下列各句中，没有语病、句意明确的一项是（ ）

Part of the reason Charles Dickens loved his own novel, David Copperfield, was ________ it was rather closely modeled on his own life.

Have you ever ________ an amusement park—Yes, I have. I ________ Fun Times Amusement Park last year.

Mary once taught English in a remote village school as a volunteer, which is ________ only on foot.