实验动物和动物实验质量存在有（）联系。
A.内在的和本质的
B.外在的
C.较少的
D.统一的
参考答案：A
According to Krashen, ______ is responsible for the fluency of the utterances produced by speakers while learning is responsible for the accuracy of the speeches or passages.
A．practising
B．analysing
C．acquisition
D．habit-formation
可持续发展战略的基本思想有哪些？
