The new templates add an ability to chain in a GPT prompt before and after machine translation. The text of the segment in the prompt is indicated with a variable {text}.
Please note that OpenAI's model won't "see" the context, only the current segment text. For example, when post-editing MT output, OpenAI won't yet be able to see the source, these functions are being built for later releases.
In order to try new functionality, you need to go to the Translation - Templates section of the portal. Press New Template and name the template you are creating, then press Create.
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Point your mouse to the plus sign on the left side of the page 
, you will see the options available for adding to your prompt.
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Pre-editing
Pre-editing option gives you the ability to change the source text before sending it to translation.
You can see below a few examples of Pre-editing prompts:
Rewrite in the Simplified Technical English {text}
Rewrite for clarity
Change units of measure from Imperial to Metric system in the text here: {text}
Proofread the text {text}
Rewrite the following in inclusive language: {text}
Press the plus sign to add the Pre-editing step
In the Pre-editing Setup window, you will need to choose the OpenAI GPT Model and you can select one of the prompts from the preset list or one of the prompts you created in GPT Playground .
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