Help me find alternatives phrases for "as long as" in formal English

[blackpassword]

Please kindly inform me what is "as long as" in formal English.

I am now translating an article about law from my native language into English and having difficulty in translating a word which is "as long as" in English.

Here is the example.

I will pay my tax as long as it will be used properly.

[susiedqq]

In this sentence:

I will pay my tax as long as it will be used properly.

as long as means "provided"

I will give you the money provided that you spend it wisely.
I will give you the money as long as you spend it wisely.

[blackpassword]

Thank you susiedqq for you very fast reply.

I knew about "provided that".
Is there any other alternative?

[SeseinAsia]

I will pay my tax as long as it will be used properly.

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I will pay my tax assuming that it will be used properly.
I will pay my tax given that it will be used properly.
I will pay my tax if guaranteed that it will be used properly.
I will pay my tax with the assumption that it will be used properly.

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Umm.. those are the closest ones I can think of. I hope they are helpful!

[light]

one more:

on condition that