短語詞組短語fall behind in study 在學(xué)習(xí)上落后fall behind in science 在科學(xué)方面落后fall behind in sth 前幾個(gè)月產(chǎn)量下降了not to fall behind in 跟上fall behind in one 's study 在學(xué)習(xí)上落后fall in behind 走在后面fall in behind Fox Company 在F連后面集合 返回 fall behind in