effective

US /əˈfek.tɪv/
UK /əˈfek.tɪv/
"effective" picture
1.

有效的, 有作用的

successful in producing a desired or intended result

:
The new policy proved to be very effective in reducing crime.
新政策在減少犯罪方面被證明非常有效
This medicine is highly effective against the flu.
這種藥對流感非常有效
2.

生效的, 有效的

(of a law or agreement) coming into operation or effect

:
The new regulations will be effective from January 1st.
新規定將於1月1日生效
The contract is effective immediately.
合同立即生效