Some phrases may function as clause constituents while others may not. The former are called constituent phrases and the latter non-constituent ones.
Most phrases can function as clause constituents; they serve different syntactic functions once they enter into the clause. Only a small number of phrases do not serve as clause constituents. These include conjunctive phrases such as huànjùhuàshuō (‘in other words’) and fǒuzédehuà (‘otherwise’), etc. Although they do not serve signifi cant syntactic functions, they play an important part in text/speech construction.