adding reagent separately的用法和样例：
- Effects of time, order of adding reagents, contents of ethanediol, silver nitrate, acid copper plating bath and nitrate on scattering intensity of resonance light were studied.
- A few jokes will add a final fillip to your speech.
- She uses tongs to add coals to the fire.
- I add the coal on the flame continuously.
- Add salt, pepper and a dash of vinegar.