这项法规是根据市长的命令颁布的。

The regulation was enacted by ___fiat of the mayor.

国王颁布法令禁止夜间外出。

The king issued a ___fiat forbidding people to go out at night.

许多国家现在使用法定货币而不是金本位制。

Many countries now use ___fiat currency instead of the gold standard.