The study explores the psychological reality of chunks for EFL Chinese students. Speech samples from three various proficiency groups are examined with the help of the computer program Cool Edit 2.0, and speaking fluency is thus determined. It is found out that speaking fluency is not linear, and fluent subjects can use, store and retrieve chunks of sentence builders as one single unit while non-fluent ones cannot, which can be attested by the fact that fluent subjects do not or seldom pause frequently within chunks of sentence builders and thus not break them up. These findings suggest that chunks are psychologically real for Chinese EFL students, and chunks should be combined into EFL learning and teaching in China.