有效

efficacious; effective; valid

♦ 这张车票三日内~。 This train ticket is good (or valid) for three days.

♦ 这个指示仍然~。 The directive still holds good.

~分蘖 [农]effective tillering~功率 [电]effective power; useful power~荷载 useful load~库容 [水]effective storage~票 valid ballot paper~期 term (or period) of validity; time of efficacy~射程 effective range~数字 significant digits