In short

You already conjugate the base binyan pa’al in the past (lesson 21): a fixed set of person endings — ־תי, ־ת, ∅, ־ה, ־נו, ־תם/־תן, ־ו — hangs off the stem and tells you who did the action. The good news for the three derived binyanim — pi’el, hif’il and hitpa’el — is that those endings are exactly the same. Nothing new to memorize on the suffix side.

What changes from binyan to binyan is only the stem the endings attach to. And unlike the present tense (the בינוני, binoni, of lesson 20), which marks gender and number but never person, the past tense does mark person: דיברתי (dibarti) is unambiguously “I spoke”, so the subject pronoun can be dropped. Recognize each binyan by its third-person-masculine-singular shape — דיבר (diber), הזמין (hizmin), התלבש (hitlabesh) — and you can build its whole past paradigm. This lesson uses strong roots only.

The rule

• The person endings are the pa’al endings — reused unchanged. Whatever the binyan, the past attaches ־תי (-ti, “I”), ־ת (-ta “you” m / -t “you” f), nothing at all for “he” (∅), ־ה (-a, “she”), ־נו (-nu, “we”), ־תם/־תן (-tem / -ten, “you” pl), ־ו (-u, “they”). Learn the endings once with pa’al; here you only swap the stem in front of them.

• Tell the three binyanim apart by the 3ms form. The bare “he did” form is the fingerprint. Pi’el has no prefix and an i–e stem: דיבר (diber). Hif’il has a ה prefix and an i…i stem written with a yod: הזמין (hizmin). Hitpa’el has the whole הת־ prefix and ends …e: התלבש (hitlabesh). No prefix vs ה־ vs הת־ — that is your first read on any past verb.

• Pi’el: stem דיבר־, “e” softens to “a” before a suffix. The 3ms דיבר (diber) has i–e; add a person ending and the second vowel opens to a: דיברתי (dibarti), דיברת (dibarta / dibart), דיברנו (dibarnu). Only “she” and “they” keep a reduced stem with a stressed ending: דיברה (dibra), דיברו (dibru).

• Hif’il: the critical i→a drop. In the 3rd person the stem keeps its i — and its yod: הזמין (hizmin), הזמינה (hizmina), הזמינו (hizminu). But in the 1st and 2nd person the i drops to a and the yod disappears: הזמנתי (hizmanti) — never hizminti — הזמנת (hizmanta / hizmant), הזמנו (hizmanu), הזמנתם (hizmantem). Same with הסביר (hisbir, “he explained”) → הסברתי (hisbarti, “I explained”), not hisbirti. This single alternation is the one real trap of the lesson.

• Hitpa’el: the whole הת־ rides along, “e” → “a” like pi’el. The prefix הת־ (hit-) stays attached through every person. The 3ms התלבש (hitlabesh) softens its e to a before a suffix: התלבשתי (hitlabashti), התלבשנו (hitlabashnu); “she” and “they” reduce: התלבשה (hitlabsha), התלבשו (hitlabshu).

• Sibilant metathesis carries over from the present. When the first root letter is a sibilant, the ת of הת־ swaps places with it — exactly as in lesson 20 — and the swap stays put in the past: ש־מ־ש gives השתמש (hishtamesh) → השתמשתי (hishtamashti, “I used”); ס־ד־ר gives הסתדר (histader) → הסתדרתי (histadarti, “I managed / got along”). Write the swapped order, not התשמשתי.

• Past marks person, so the pronoun is optional. Because ־תי can only mean “I” and ־נו only “we”, the subject is already inside the verb: דיברתי is a complete sentence, “I spoke”. This is the opposite of the present binoni (lesson 20), where the identical form serves every person and the pronoun must stay.

Forms & patterns

Pi’el — root ד־ב־ר (speak), 3ms דיבר (diber):

Hif’il — root ז־מ־ן (invite / order), 3ms הזמין (hizmin):

Notice the split: the i (with its yod) survives only in הזמין / הזמינה / הזמינו — the 3rd person. Everywhere a person suffix is added it becomes a and the yod is gone.

Hitpa’el — root ל־ב־ש (get dressed), 3ms התלבש (hitlabesh):

The three 3ms shapes side by side — your recognition anchor:

Sibilant metathesis in hitpa’el (unchanged from the present):

Examples

Common mistakes

• הזמינתי אותו -> הזמנתי אותו (hizmanti oto) - hif’il drops the stem i to a once a person suffix is added: the yod disappears and you say hizmanti, never hizminti.
• הסבירתי את הדרך -> הסברתי את הדרך (hisbarti et ha-derech) - the same drop: 1sg is hisbarti; the i of הסביר (hisbir) survives only in the 3rd person — הסביר, הסבירה, הסבירו.
• דיברתי (diberti) -> דיברתי (dibarti) - in pi’el the 3ms “e” of דיבר (diber) opens to “a” before a suffix: you say dibARti, not diberti.
• התשמשתי במילון -> השתמשתי במילון (hishtamashti be-milon) - when the first root letter is a sibilant, the ת of the הת־ prefix swaps places with it: hi-sht-amashti, never a plain hit- + shamashti.
• הוא דיברתי -> הוא דיבר / אני דיברתי - the ending already names the person: ־תי is “I”, so it cannot sit under הוא. Match the suffix to the subject.
• אני מדבר עם המורה אתמול -> אני דיברתי עם המורה אתמול (ani dibarti im ha-mora etmol) - a past event needs a past suffix, not the present binoni; מדבר is “I speak / am speaking”, not “I spoke”.
• היא הזמנה שולחן -> היא הזמינה שולחן (hi hizmina shulchan) - the drop to a is only for the 1st/2nd person; “she” and “they” keep the i and its yod: הזמינה, הזמינו.

Tips

• The suffixes are the pa’al past suffixes from lesson 21 — ־תי, ־ת, ∅, ־ה, ־נו, ־תם/־תן, ־ו. Learn them once; from here on only the stem in front of them changes.
• Read the binyan off the 3ms shape: no prefix + i–e = pi’el (diber), ה + i…i = hif’il (hizmin), full הת־ = hitpa’el (hitlabesh).
• Burn in the hif’il alternation: 3rd person keeps i + yod (הזמין, הזמינה, הזמינו); every 1st/2nd person opens to a and loses the yod (הזמנתי, הזמנת, הזמנו, הזמנתם). Same story with הסביר → הסברתי.
• In pi’el and hitpa’el the 3ms “e” likewise softens to “a” in front of a suffix: diber → dibARti, hitlabesh → hitlabASHti.
• “She” and “they” reduce the stem and stress the ending in pi’el and hitpa’el: dibrá / dibrú, hitlabshá / hitlabshú. Hif’il is the exception — it keeps the full i (with its yod) and the stress stays on the stem: hizmína / hizmínu.
• Because the suffix carries the person, you may drop the subject pronoun in the past — the reverse of the present binoni (lesson 20), where the pronoun is obligatory.
• Metathesis verbs from lesson 20 keep the swap in the past too: השתמש → השתמשתי, הסתדר → הסתדרתי. Never write the letters in root order.
• Everything here assumes a strong root. Guttural and weak roots (and the passive binyanim) shift the vowels further — those are separate lessons.