Then watch your gift multiply.
( Then ( ( watch ( your ( gift multiply ) ) ) . ) )
(ROOT (S (RB Then) (VP (VB watch) (NP (PRP$ your) (NN gift) (NN multiply))) (. .)))
Watch your gift dwindle. 
( ( Watch ( your ( gift dwindle ) ) ) . )
(ROOT (S (VP (VB Watch) (NP (PRP$ your) (NN gift) (NN dwindle))) (. .)))