Which factor -- if any -- plays the dominant role is so far unclear.

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When it comes to gender expression, don't assume that the person wearing the pants at the wedding plays a dominant role in the relationship, she said.

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The last Holyrood election saw the SNP become the first party to win an overall majority, meaning it plays a dominant role in the parliament's chamber and cross-party committees.

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But China's military which plays the dominant role in its relationship with North Korea has grown more determined to maintain Pyongyang as a buffer against U.S. forces in Asia since the Obama administration's strategic "pivot" toward the region, according to Chinese military analysts.

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