mutteringlyadv.mutter的变形：mutter['mʌtə]murmur的变形：vi.低声说；含糊不清地说；咕哝：The old man muttered to himself.老人喃喃自语。小声抱怨；发牢骚 (与against或at连用)：She muttered against her husband.她抱怨丈夫。发出低沉的轰鸣：They heard thunder muttering among the hills.他们听见山中雷声隆隆。vt.低声说；喃喃地说；抱怨地说：低声说；喃喃