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general::
Also, keep up. Go at the same rate as others, not fall behind. For example, The teacher told his mother that Jimmy was not keeping up with the class. Shakespeare had the first term in A Midsummer Night's Dream (3:2): "My legs cannot keep pace with my desires." [Late 1500s]
American Heritage Idioms
2
general::
Phrase(s): keep pace (with someone or something)
1. Lit. to move at the same speed as someone, something, or an animal; to match someone or some creature pace for pace. • The black horse was having a hard time keeping pace with the brown one. • Tom runs very fast and I couldn’t keep pace with him. 2. Fig. to manage to move, learn, change, etc., at the same rate as someone or something. • Bill can’t keep pace with the geometry class. • You’ve just got to keep pace.
McGrawhill's American Idioms And Phrasal Verbs