有效

This medicine ought to do the trick.

The new tablets are tremendously effective.

The contract/law still holds.

This contract will no longer stand.

effective date; date of validity

effective treatment method

valid passport/documents/identity card

valid contract/agreement

effective measure/management

effective remedy

valid copyright

hold good at all times and all places

remain in force; be still in effect

be valid for one year/three months

establish effective and restraint mechanisms

do effective work

be efficacious in preventing smallpox

effect a good interface between public ownership and market economy