[Grammar] The appropriate article

Hello,
I am having trouble choosing the appropriate articles (a/the/none) in the following lines:

Reactor no. 546
Wash .....reactor with .......purified water. Perform.....washing through ...... pump.
Upon......washing completion, empty ....... reactor.

I would really appreciate if you could fill in the appropriate articles and explain why they are correct.

Reactor no. 546
Wash THE reactor with purified water. Perform THE washing through THE pump. Upon washing completion, empty THE reactor.

In the example you have given, the sentence already sounds odd to English ears.

"Wash the reactor with purified water" sounds perfectly idiomatic.
I chose "the" because it is the definite article – we are talking about a particular reactor. You need an article and in this case it makes most sense with the definite article. Purified water does not need an article: it is a mass noun. However, if the purified water was supplied as part of a washing kit, and was known to us, it would be possible to talk of "the purified water [that you have in front of you]"

"Perform the washing through the pump" sounds odd and it is not clear what is meant. Does it mean that the pump should also be washed, or that the use of a pump is necessary to complete the washing process? I am assuming that the pump is a particular pump that is nearby; if pumps are available in a store room somewhere and you would be well advised to go and fetch one, then you could also say "Perform the washing through A pump [which could be one of many in the store]".

"Upon washing completion, empty THE reactor."
It sounds strange (but not necessarily wrong) to say "Upon washing completion". A more idiomatic construction would be "Upon completion of the washing process" or "When [the] washing is complete…". Again, it is "THE reactor" that gets emptied because it is the reactor we have in front of us and have been discussing (definite article), not any old reactor (indefinite article).

I hope that helps and my explanation isn't too complicated or muddled!

Thank you for the prompt answer!
It helps me a lot.
I have a lot of "washing/stirring/heating/cooling the reactor" phrases. Also a lot of "upon washing/stirring/heating/cooling completion" phrases . So if I understood you correctly, I don't need "the" before "washing" in - "upon washing completion" - though it is a definite washing mentioned earlier.
And if I use the phrase you suggested - "upon completion of the washing process" - i do need "the" before "washing process" (can I omit the "process" and use only - "upon completion of the washing" - would that be correct and better that the initial phrase - "upon washing completion"?
How would you change these lines to sound better?
Re pumps - there are pumps in a room to use, not a specific one. In odred to wash a reactor a pump is connected to a water tank, and the reactor is washed.
Thank you very much for your help.

hotmetal said:

Perform THE washing through THE pump

Click to expand...

Upon reading such instruction, the first thought is that I have to crawl with a brush through the pump to wash it (pump)
Wouldn't it be better to write "with" or "by" instead of "through"?
An to write "Wash the reactor with/by a nearby pump"?

Maybe you are right, I will look into it.
And what do you think about:
"upon completion of the washing process" - i do need "the" before "washing process" (can I omit the "process" and use only - "upon completion of the washing" - would that be correct and better that the initial phrase - "upon washing completion"?
Does words like washing, drying, stirring, heating, cooling, need to an article in sentences like "Stop......heating and activate ......washing."?

Also, "organ" and "tissue" are not preceeded by an indefinite article? They are indefinite coun nouns. (*Taken from an actuall reactor manual)

Exposure of a person, organ or
tissue to radiation may exceed the​

applicable radiation*

kissandra said:

Hello,
I am having trouble choosing the appropriate articles (a/the/none) in the following lines:

Reactor no. 546
Wash .....reactor with .......purified water. Perform.....washing through ...... pump.
Upon......washing completion, empty ....... reactor.

I would really appreciate if you could fill in the appropriate articles and explain why they are correct.

Click to expand...

wash the reactor with purified water.perform the washing through a pump.
upon washing completion, empty the reactor.
(the is used for something specific u know about..like u kn the reactor ur using..perform the( that particular washing which we are talking abt) washing through a pump(cause the pump can be any random pump)

sanasyed1992 said:

wash the reactor with purified water.perform the washing through a pump.
upon washing completion, empty the reactor.
(the is used for something specific u know about..like u kn the reactor ur using..perform the( that particular washing which we are talking abt) washing through a pump(cause the pump can be any random pump)

Click to expand...

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