工厂的烟囱排放出大量的黑烟。

The factory ___chimneys are emitting a lot of black smoke.

工厂的高烟囱向天空排放着滚滚黑烟。

The factory's tall ___chimneys were releasing thick black smoke into the sky.

攀岩者缓慢地沿着悬崖上狭窄的岩缝向上攀登。

The climbers slowly ascended through the narrow ___chimneys in the cliff.