If you've got ads for different languages and regions, you should split up the different ad sets into the different languages you have by adding filters on language. Therefore, when making your various ads, you can then ensure that your English ad is only on the English ad set (that is to say, that none of your English customers sees a French ad).
Furthermore, you can use the Dynamic Language Optimisation provided by us when you create an ad. This optimisation creates different variations from your ad in different languages which you can therefore optimise to get the best results.
To start setting up the DLO, click on Create in different languages once you click on New ad.
Afterwards, click on the drop-down menu below Default language and choose the language which your ads have been created in. Then click on the blue button that says Add language.
Once you've clicked on the blue button, a drop-down menu will appear in which you'll need to select which language you want to create your variations in. Choose all the languages you want to use and then, this screen will show up:
Here you can fill in all the details in your new language: a new Website URL, Display URL, a Headline, and Text. This is highly useful if you've got a different website per language—so people who speak this language will be redirected to the correct page and will find the site in their own language.
Once you've finished, click on Save.
Please remember that the Dynamic Language Optimisation is not available for all objectives.