Sentence:  Woodbury (1975) does argue, however, that absolutives are more relativisable in Greenlandic than are <WSD>ergatives</WSD>, on the grounds that (1) RCs[Relative Clauses] formed on <WSD>ergatives</WSD> are somewhat more restricted in the distribution in matrix clauses (p. 21) than are those formed on absolutives, and (2) for certain verb classes <WSD>ergatives</WSD> cannot be relativised out of the active participle (p. 27). 
Meaning of the word marked with <WSD> tags:  An ergative verb or other expression.