This policy precludes the routine use of chemicals.这项政策阻碍了化学品的常规使用。A constitutional amendment precludes any president from serving more than two terms.一项宪法修正案使得任何总统的任职不得超过两届。The adoption of one choice often precludes the use of another.选取了一种常常就不得使用另一种了。