单项选择题 The two sounds [ p ] and [ b ] share the same place and manner of articulation, but they are distinguished by _______.

未知题型 常见弓网故障主要由受电弓和接触网关系不良引起，包括：1、 ；2、 ；3、 。

未知题型 Choose a summary word from the list to complete the sentence. process; situation; finding; estimation; problem; difficulty; disruption; view Normal average human skin temperature is 37°C. At any lower environmental temperature, heat will be lost from the skin to the environment as the body attempts to heat up the air in direct contact with the body. This is known as conduction.