242. 你有必要这样去做。
[误] It is necessary of you to do so.
[正] It is necessary for you to do so.
注:一个形容词可以用来指“行为”,又可以用来指“行为者”,如 kind, good, foolish, nice, careful, careless 这类皆是。这种形容词可以接用 of 来造句,如 It is kind of you. (行为)= You are kind. (行为者)。另外有些形容词,只能用来指“行为”,不能用来指“行为者”,如 necessary, impossible, inconvenient, unbearable 这类皆是。这种形容词是不可以接用 of 来造句的,它只能接用 for,例如 It is necessary for you to go. 而不能说 You are necessary to go.