BEIJING -?China's National Anthem Law came into force Sunday to ensure appropriate performance of the song.

The anthem shall be sung at formal political gatherings, including the opening and closing of National People's Congress sessions, constitutional oath ceremonies, flag raising ceremonies, major celebrations, awards ceremonies, commemorations, national memorial day events, important diplomatic occasions, major sport events and other suitable occasions, according to the law.

It is now illegal to use the national anthem during funerals, "inappropriate" private occasions, commercials or as background music in public places.

Violators, including those who maliciously modify the lyrics, play or sing the national anthem in a distorted or disrespectful way, can be detained for up to 15 days, even be held criminally liable.

The song will be included in textbooks for primary and secondary schools, and people are encouraged to sing the national anthem on appropriate occasions to express patriotism.

The national anthem "March of the Volunteers," has lyrics by poet Tian Han and music by Nie Er.

The original song greatly encouraged Chinese soldiers and civilians during the Chinese People's War of Resistance against Japanese Aggression (1931-1945).

It was chosen as the national anthem in 1949, and was broadcast across the world as Mao Zedong declared the founding of People's Republic of China on Oct. 1, 1949. The national anthem was revised in 1978. The "March of the Volunteers" was reaffirmed as the national anthem in 1982.

China already has laws covering its national flag and national emblem.

Previously, without a law to standardize etiquette for the national anthem, the song was sometimes used inappropriately.