"I like the apple."
Translation:Dw i'n hoffi'r afal.
dw i'n... is the usual form, although some people do write it informally as it is pronounced - dwi'n...
Both forms are on the course database, with dw i'n hoffi'r afal currently set as the default form. If you are using the app, you may need to make sure that you have the latest version. Otherwise, it may be that something has changed in the database recently and it has yet to reach the wider Duolingo system. No problem to use dwi, though, at least informally.
hoffi and licio both mean the same thing - ‘liking, to like’. Both are used all over Wales.
’r is just a form of yr/y -‘the’
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