needless

形容词 needless:

1. unnecessary and unwarranted
   同义词：gratuitous, uncalled-for

1. He got a large fortune when his father died, but trifled it away in only a few years of needless spending.
   父亲去世时他得到一大笔财产，可仅仅几年的时间就将这笔钱胡乱挥霍一空。
2. Needless to say, learning without thinking is useless.
   不用说，学而不思则罔。
3. Needless to say, he kept his promise.
   不用说，他信守了他的诺言。