减去

This relieved us of part of our luggage.

这给我一部分行李的负担。

The advertised price was 168 dollars, but the shopkeeper knocked off the odd shillings.

广告价格是168美元, 但是店主了零头。

The picoammeter reads the current at the last dynode, which is equal to the anode current minus the current flowing to the previous dynode.

皮安计在最后一个倍增管电极读取电流，此电流等于阳极电流流过前一个倍增管电极的电流。