|  | | | Posted on Thu Mar 13, 2008 17:30:28 |  | 
 |  |  |  | I think iucundum modifies amorem, and proponis is indicative, not imperative, so perhaps not: 
 promise that this love of ours between us shall be agreeable and last forever
 
 but rather,
 
 you promise this pleasant love of ours between us will last forever
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