Word: locking text so it stays together.

[clioswamp]

tried to google but couldn't find an answer. i have a sentence:

....and draw a grid (-5 5) on both axis....

how do you lock the '(-5 5)' together so they appear as one word and aren't split upon formatting, for instance:

....and draw a grid (-5
5) on both axis...

 

[SC03OTT]

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