Help: Note beaming

I've read through https://musescore.org/en/handbook/3/time-signatures#change-default-beam… a few times now, and I'm still having problems with note beaming.

I wrote a simple exercise that has two triads as 8th notes and ends with two additional 8th notes, a total of 8 notes in this measure of 4/4. By default, Musescore placed beams over the first and last groups of four 8th notes. What I'd like to do is have the beam over each triad, giving a beam over the first triad, (no beam between the 3rd and 4th notes), a new beam over the second triad and ending with a third beam over the last two 8th notes.

I've been struggling to break apart the two current beams and reassemble the set of 8 notes in three separate beams. I'd appreciate some help.

Thanks.