登山者开始缓慢地沿着陡峭的山坡下降。

The climbers began their slow ___descent down the steep mountain slope.

他有着英国血统，但从未去过英国。

He is of British ___descent but has never been to the UK.

从陡坡滑雪下来时要格外小心。

Be extra careful when skiing down the steep ___descent.

士兵们迅速突袭了敌方阵地。

The soldiers made a swift ___descent on the enemy's position.