in force

形容词 in force:

1. exerting force or influence
   同义词：effective, good, in effect

1. On the day the school was opened to visitors, all the parents turned out in force.
   学校对来访者开放的那一天，所有的家长成群地去了。
2. The law should remain in force.
   法律应当有效力。
3. The new safety regulations are now in force.
   新的安全规则现已生效。
4. Many old rules are not in force any more.
   许多旧的制度都已经失效。