is that grammar correct?

If the activity hasn't been hold before, the manager will invite the person who is in charge of the organization to tell the risk of that activity to leading staffs.
If the low risk of that activity hasn't been told before, leading staffs will have to analysis the risk of that activity by themselves.
If the low risk of that activity has been told before, the staff will analysis the past accident records. Every two months, the swimming pool's sand filter will be cleaned.
High event is checked by professional worker once a year.


Sorry i tried my best, i don't really understand but i hope this will help u.

2006-11-07 22:58:06 補充：
If the activity has not been told before, the manager will invite the person who is in charge of the organization to tell the risk of that activity to leading staffs.

If the activities have not been held before, the manager would invite the person who is in charge of the organization to explain the risk of those activities to their leading staffs.
If the low risk has not been held before, the leading staffs would analyze the risk of those activities by themselves.
If the low risk program held before, the staffs would analyze the past accident records.
Swimming pool's sand filter is cleaned every two months.
High event is checked by professional worker once a year.

If the activity has not been held before, the manager would invite the person in charge of the organization, to explain the risks of the activities to the leading staffs.

...The rest doesnt seem right... I don't actually understand what you mean... do you have the chinese version i can translate for u?

Anyway~ gdluck~