(answers)

ἀκούει

• stem is ἀκου (don't worry about the accent, but do include the breathing mark)
• personal ending is ει
• lexical form is ἀκούω
• meaning of inflected form is "he/she/it hears"

ἀκούουσι

• stem is ἀκου
• personal ending is ουσι
• lexical form is ἀκούω
• meaning of inflected form is "they hear"