Abstract: Four experiments were conducted using a line-by-line reading paradigm to examine the role of sentence boundaries.In Experiment 1,readers were delayed in noticing a contradiction on a target line when the sentence continued onto a post-target line.Consistent with this,in Experiment 2,target line was an intact sentence.The result of a recognition probe demonstrated that there was no significant difference between the consistent version and inconsistent version.The participants noticed the contradiction as soon as they completed reading the target line.From Experiment 1 and Experiment 2,it could be concluded that sentence boundary play an important role in reading.They may be a signal which lets the readers integrate the current sentence before they read the following sentence.The goal of Experiment 3 was to investigate whether it was necessary in discourse comprehension.The result of Experiment 3 demonstrated that sentence boundary was sufficient to facilitate the integration of related background information but not necessary.Now that the period can affect the discourse comprehension,what about the semicoto n?In Experiment 4,the result showed that the semicolon made no difference in integration of current sentence.In a word,period is an influential factor to reading but semicolon not.

Key words: sentence boundary, Discourse comprehension, anap hora, global coherence, local coherence