Seek verb in: there is a ming vase which is on the table
    viability map of 'there is a ming vase which is on the table':
    -- is[1] -- -- -- -- is[1] -- -- -- 
    Found usage, pass 1 tier 2: (there) be(0) (a ming vase which is on the table)
        Seek verb in: a ming vase which is on the table | 
            viability map of 'a ming vase which is on the table':
            -- -- -- -- is[1] -- -- -- 
            Found usage, pass 1 tier 2: (a ming vase which) be(0) (on the table)
            Accepted as be(0) + on + ___
        Seek succeeded: VERB_NT'is on' {verb 'be' 3p s act IS_TENSE +ve} {prep1: on}

Seek succeeded: VERB_NT'is on' {verb 'be' 3p s act IS_TENSE +ve} {prep1: on} {existential}

Sentence subtree:
    VERB_NT'is on' {verb 'be' 3p s act IS_TENSE +ve} {prep1: on} {existential}
    UNPARSED_NOUN_NT'ming vase' {indefinite 'a' n/m/f nom/acc s}
    RELATIONSHIP_NT'is on' {meaning: carries}
        UNPARSED_NOUN_NT'table' {definite 'the' n/m/f s/p nom/acc}