A. To practice speaking slowly. B. To record a voice from the television. C. To play a speech by the professor. D. To evaluate their own voices. 参考答案:D
第33题: [单项选择]流产的定义是() A. 妊娠<37周,胎儿体重<2500克而终止妊娠 B. 妊娠<28周,胎儿体重<1000克而终止妊娠 C. 妊娠<24周,胎儿体重<1500克而终止妊娠 D. 妊娠<24周,胎儿体重<1000克而终止妊娠 E. 妊娠<20周,胎儿体重<500克而终止妊娠 参考答案:B