________ have an internal clock that controls the beating of our heart, and the

题干

________ have an internal clock that controls the beating of our heart, and the ________ of our breathing.

A．Human being; steps	B．Humans; pace
C．Human beings; steps	D．Man; pace

上一题下一题 0.85难度单项选择更新时间:2014-04-18 08:59:18

小学学科试题库

初中学科试题库

高中学科试题库