Use the first mouth shape to play single notes and the second one to play chord with tongue block.

吹十孔口琴一般都是用第一种，吹和弦或者使用舌堵法时就要用第二种口形了。

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The variation of the river mouth shape has obvious impact on the estuarine circulation, the salinity intrusion and the turbidity maximum zone.

河口形状对河口环流、盐水入侵和最大浑浊带的影响明显。

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Firstly, form a right mouth shape, and then make it familar and suitable with the comb to play clear single notes.

首先要掌握正确的口型，尔后再用这个正确的口型来适应口琴的吹嘴，吹出干净的单音。

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She spent time in front of a mirror, retraining the shape of her mouth, forcing her lips into a long oval "O" to evoke Ms. Garland's face in midbelt but pulling back when the look turned clownish.

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Over the years the word had moulded itself to the shape of an African mouth.

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The mouth is often in an "O" shape from shock.

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