Abstract: Previous studies showed that in dual focus sentences, Post-Focus FO Compression(PFC) was absent after the first focus. Was it related to the number of syllables between the two foci? In the present experimental study,focus position and sentence length were controlled. The results showed that the two foci were independent as well as dependent on each other. They were independent because each focus had its own domain, and its FO rising and duration lengthening reached to the same degree as its single focus counterparts. They were dependent because the two foci could coexist in one intonation phrase. The lack of PFC after the first focus was due to the insertion of a prosodic phrase boundary, rather than to the number of syllables between the two foci. The perception experiments showed that the correct perception rate of dual focus was significantly lower than that of initial focus, probably because it was hard to detect two foci in one sentence. When the listeners were asked to only pay attention to the first focus, the correct perception rate was much higher, and it was similar to that of the initial focus counterpart. Therefore, we concluded that the perception of the two foci was asymmetric. The increase of FO and duration guaranteed correct perception of an initial focus, but not a final focus. In general, the first focus was perceptually more prominent in a dual focus sentence.