Extra notes in a specific bar

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Hi Sherry, I know in the past you addressed this question but I couldn't find the thread and/or the tutorial, plus I have a brand-new computer and didn't do back up arghhh! Here is the issue: I'm transcribing a piano piece. Its in 2/4 and on this particular bar the treble clef has two eight notes triplets while the bass clef has a half note (stem down) plus a quarter note rest and two quarter notes stem up. Could you explain or point me to the right tutorial? I'm trying to get back in the "grove" after a prolonged absence for reasons beyond my control. Thanks!