Learn Farsi: تا ژنراتور را پایش می‌کنم، خوب کار می‌کند. - As long as I monitor the generator, it works well.

The key is the verb tense. When تا means 'until' or 'so that,' it is usually followed by the subjunctive mood. Here, it is followed by the present indicative verb پایش می‌کنم (I monitor). This specific combination of تا + indicative creates the conditional meaning 'as long as' or 'while.'

Why do both parts of the sentence use the present tense (می‌کنم and می‌کند)?

This sentence describes a general, habitual fact. The condition ('as long as I monitor it') and the result ('it works well') are both ongoing realities. For these conditional statements of duration, using the present indicative in both clauses is the standard way to show a continuous, linked truth.

I haven't seen پایش کردن before. Is this the standard way to say 'to monitor'?

پایش کردن is a formal, technical compound verb used for monitoring a system, process, or patient. In casual everyday speech, people might just use a phrase like مواظب بودن (to keep an eye on), but پایش کردن is exactly what you would expect when talking about machinery like a generator.

Why is there no word for 'it' before خوب کار می‌کند?

Because Farsi frequently drops pronouns when the subject is already obvious from the context. Since ژنراتور (generator) is the established topic of the first clause, it carries over naturally as the implied subject of the second clause.