Object NPs can be marked by the nominative case marker/particle ga in the so-called desiderative or tai 'want' construction in Japanese. Replacement of o by ga called ga-o conversion is possible in this construction. However, there are some cases where the ga-o conversion results in unacceptability. The environments where the conversion can/cannot take place has been extensively discussed in the literature and several conditions on the ga-o conversion have been proposed thus far (Kuno 1973a,b,