答案：C

lose one's place意为读书时“找不到读到哪儿”。类似的习语有：lose heart(灰心，泄气),lose one's heart to sb. (爱上某人),lose one's head(惊慌失措),lose one's hold on(or over)(失去对......的控制),lose one's temper(发脾气),lose one's tongue (紧张得不知说什么好)，lose one's way (迷路),lose sight of(看不见了),lose one's never(失去勇气)。