Simplify the following text for a Grade 18 native English-speaking person.
Original: Singaporeans are especially encouraged to sing the national anthem on occasions of national celebration or national significance such as at the National Day Parade , at National Day observance ceremonies conducted by educational institutions and government departments , and at sporting events at which Singapore teams are participating .
Simplified: Singaporeans are encouraged to sing the national anthem during times of national celebration or at important national events such as at the National Day Parade , at National Day observance ceremonies held by government departments and educational institutions such as schools and universities , and at sports events that Singapore teams take part in .