be on the decrease

基本解释

In winter, the refrigerating device can be powered on to decrease the water temperature.
在夏季還可開啓制冷裝置降低水溫。
ip.com
Did you ever think how nice it would be to increase or decrease the font size on your mobile phone?
你曾經想過如果能增大或減小你手機的字躰有多好嗎？
This membrane can be used to fabricate a phenol optical sensor based on the decrease of chemiluminescence intensity.
此敏感膜可用於制備基於化學發光強度減弱的苯酚光化學傳感器；

In any case the decision to decrease expenditures on defense and law enforcement can only be taken by the president said a highly placed government official.
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President GEORGE W. BUSH: As we make progress on the ground and Iraqi forces increasingly take the lead, we should be able to further decrease our troop levels.
NPR: Bush Faces Tougher Audience in This Year's Address
The year-on-year growth rate will be 43% in 2011, but will decrease to 13% over the next five years.
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