drop behind

Từ điển tiếng Anh - Cambridge Advanced Learners Dictionary

drop behind phrasal verb [ dropping behind dropped behind dropped behind dropped behind drops behind ]
to get further behind or away from something or someone
• As the pace quickened, Pepe began to drop behind.
• She stopped going to classes and dropped behind in her schoolwork.
Thesaurus⁺: ↑Slow and moving slowly
Main entry: drop_{phrasal verb}