他花了一下午时间仔细研读这份报告，寻找任何可能的错误。

He spent the afternoon ___poring over the report, looking for any possible mistakes.

他整个下午都在仔细研读那本历史书。

He spent the whole afternoon ___poring over the history book.

她趴在桌上，全神贯注地研究着那份旧地图。

She was ___poring over the old map spread on the table.