他在办公室里埋头苦干了一整天，处理那些堆积如山的文件。

He's been ___slogging away at the office all day, dealing with piles of paperwork.

孩子们在厚厚的雪地里艰难地行走。

The children ___slogged through the deep snow.

完成这个项目是个苦差事，我们连续加班了好几周。

Finishing this project was a real ___slog, with us working overtime for weeks.