The occurrence of public health emergencies is relatively sudden, there is no specific way of occurrence, sudden, with great chance, not easy to predict, making it difficult for people to prevent in time;
The occurrence of public health emergencies is relatively sudden, there is no specific way to occur, suddenly, with a great deal of chance, not easy to predict, making it difficult to prevent in a timely manner;
The occurrence of public health emergencies is relatively sudden, there is no specific way of occurrence, sudden, with great contingency, not easy to predict, making it difficult for people to prevent in time;<br>