use [Your_Database]

GO

GRANT INSERT TO [Your_User]

GO

use [Your_Database]

GO

GRANT SELECT TO [Your_User]

GO

use [Your_Database]

GO

GRANT UPDATE TO [Your_User]

GO

use [Your_Database]

GO

DENY DELETE TO [Your_User]

GO

Your_User --- is user that you want grant select insert & update but not to drop or delete!