Last edited by DavyBCN; 28-Aug-2006 at 13:15. Reason: spelling
In the case of numerical quantifiers, only 1 takes the singular.
The other examples you quote are different: 'x of a litre' is the possessive genitive case, where the possessor is a (singular) litre. A 'half litre' (or a 'quarter litre') uses the quantifier as an adjective, again describing a singular litre.
Last edited by Coffa; 28-Aug-2006 at 13:22. Reason: typo