1) I insist that you shall be present.
务必请您到
2) I insist that you (should) be present
请您务必到场。
3) Be so kind as to let me know.
务必请通知我。
4) Musks must be worn
请务必戴面罩
5) Respirators must be worn
请务必戴呼吸器
6) Do have some mushroom .
请务必用点蘑菇。
参考词条