Pick an infinitive. Spell one past-tense form, name the pronoun of another, sort the whole set if you like, then study the full table.
English past uses one ending for everyone: I walked, she walked, they walked. Hebrew past puts the person on the verb itself: stem + ending, and the ending tells you who.
Two pairs look identical without niqqud: כתבת = אַתָּה כָּתַבְתָּ or אַתְּ כָּתַבְתְּ, and כתבו = הֵם or הֵן. Both answers count; the niqqud that appears after you answer shows the difference.
Bonus: each binyan's name is its own הוּא past form, built on the dummy root פ.ע.ל. Tap a row for the clue and the trap.
Double-tap any finished verb to open its full table. Bold = root. Completed columns regroup by subtype (גִּזְרָה).