The agreement could be formal, through a contract, or informal, when the dealer's compliance is coerced. 这种协定可能是以合同的形式正式鉴定的，当代理商们对这种协定价格的服从是被强制的时候，协定也可能是非正式的。
Some English vowel sounds which are not given weight in speech become reduced to a rather formless central vowel. 英语中有些元音在讲话时没有重读，结果成了相当不定型的中央元音了。
