Correct

时效

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Strokes

Definition

effectiveness for a given period of time/prescription (law)/aging (metallurgy)

Example

As a Noun

effectiveness for a given period of time

1
Yàopǐn
药品
shíxiào
时效

expiry dates of medicines

2
Shīqù
失去
shíxiào
时效

be no longer effective; cease to be in force

As a Noun

prescription; limitation

3
Sùsòng
诉讼
shíxiào
时效

limitation of actions

As a Noun

ageing

4
Shíxiào
时效
yìnghuà
硬化

age-hardening

5
Shíxiào
时效
gāng
钢

aged steel