  The same multi-word expressions may have different meanings in different
sentences. They can be mainly divided into two categories, which are literal
meaning and idiomatic meaning. Non-contextual-based methods perform poorly on
this problem, and we need contextual embedding to understand the idiomatic
meaning of multi-word expressions correctly. We use a pre-trained language
model, which can provide a context-aware sentence embedding, to detect whether
multi-word expression in the sentence is idiomatic usage.
