In short

A real (open) conditional says “if X happens, (then) Y will happen” about a genuinely possible future — you don’t yet know whether X will come true, but if it does, Y follows. Hebrew builds it with אם (im, “if”) on the condition half and the future tense inside it: אם ירד גשם, נישאר בבית (im yered geshem, nishaer babayit, “if it rains, we’ll stay home”). The two halves are the protasis (the אם-clause, the condition) and the apodosis (the result).

The single reflex that carries this lesson: after אם, a still-to-happen event goes in the FUTURE tense, exactly as the event itself is future. English drops “if” into the present (“if it rains…”), but Hebrew keeps the real tense — אם ירד, not *אם יורד. Keep this frame apart from temporal כש־ (kshe-, “when”, which treats the event as certain) and from the yes/no question-marker האם (ha’im).

The rule

• The frame: אם + future → future. The protasis opens with אם (im, “if”) and puts its verb in the future for anything that hasn’t happened yet; the apodosis (the result) is normally also in the future: אם תלמד, תצליח במבחן (im tilmad, tatzliach ba-mivchan, “if you study, you’ll pass the exam”). Both verbs look forward, because both events are ahead. This is the neutral, “textbook” real conditional — use it whenever you’re predicting a consequence of a possible future action.

• The apodosis can be an instruction — imperative or future. When the result half is a command or request rather than a prediction, use the imperative (lesson 38) or, just as commonly in Modern Hebrew, the 2nd-person future doing imperative duty: אם יהיה לך זמן, תתקשר אליי (im yihye lecha zman, titkasher elay, “if you have time, call me”); אם תגמור מוקדם, בוא אליי (im tigmor mukdam, bo elay, “if you finish early, come over”). The condition still carries the future (יהיה, תגמור); only the result switches to a command.

• General truths keep the present in both halves. If the “if” isn’t a one-off future event but a repeating fact — a rule that always holds — Hebrew, like English, uses the present throughout: אם אין חשמל, המקרר לא עובד (im ein chashmal, ha-mekarer lo oved, “if there’s no electricity, the fridge doesn’t work”). The future-tense rule is specifically for a particular event still to come, not for a timeless generalisation.

• אז “then” is an optional bridge into the result. You may mark the boundary between the two halves with אז (az, “then”) at the head of the apodosis, very common in speech: אם תרצה, אז נדבר מחר (im tirtze, az nedaber machar, “if you want, then we’ll talk tomorrow”). It adds nothing to the meaning and can always be dropped — אם תרצה, נדבר מחר is equally correct.

• Negate the condition with אם לא + future. “If … not / unless” is simply אם לא (im lo) in front of the future verb: אם לא תמהר, נאחר לרכבת (im lo temaher, ne’acher la-rakevet, “if you don’t hurry, we’ll be late for the train”). The לא still sits before a future verb, never before a present one — it is אם לא תמהר, not *אם אתה לא ממהר.

• במקרה ש־ “in case” — a near-synonym, and it takes ש. For a precaution (“in case …”) use במקרה ש־ (bemikre she-) with the same future verb: במקרה שתאחר, תשלח לי הודעה (bemikre she-te’acher, tishlach li hoda’a, “in case you’re late, send me a message”). Note the asymmetry: because מקרה is a noun, this connector needs ש to hook a clause on — unlike bare אם, which attaches straight to the verb-clause with no ש.

• Keep אם apart from כש־ and from האם — three different words. אם (im) = “if”, the event is uncertain (it may or may not happen). כש־ (kshe-, lesson 45) = “when”, the event is taken as certain and only its timing is in question: אם יבוא, נשמח (“if he comes, we’ll be glad” — maybe) vs. כשיבוא, נשמח (“when he comes, we’ll be glad” — he will). And האם (ha’im, lesson 8) is the yes/no question-marker (“האם הוא בא?”, “is he coming?”) — same sound, unrelated job. Don’t let them blur.

• Real vs unreal — this lesson is only the real one. Everything here is an open condition about the future (“if it rains” — it might). The unreal / counterfactual type — “if it had rained (but it didn’t)”, “if I were rich” — is built quite differently, with לו / אילו (lu / ilu) + the past, and is handled in the counterfactual lesson. Don’t reach for לו here; for a genuine open possibility it is always אם.

Forms & patterns

The real-conditional frame (protasis + apodosis):

The condition markers:

Don’t confuse — same sound, different job:

Examples

Common mistakes

• אם אתה בא מחר, נלך לים -> אם תבוא מחר, נלך לים (im tavo machar) - a still-to-happen event after אם takes the FUTURE תבוא; the present אתה בא is colloquial only, not the neutral form.
• כשירד גשם, נישאר בבית (meaning “if it rains”) -> אם ירד גשם, נישאר בבית (im yered geshem) - an uncertain condition is אם “if”; כש־ means “when” and treats the event as sure to happen.
• האם תלמד, תצליח -> אם תלמד, תצליח (im tilmad, tatzliach) - conditional “if” is אם; האם is the separate yes/no question-marker, not a conditional.
• אם אתה לא ממהר, נאחר -> אם לא תמהר, נאחר (im lo temaher) - negate the condition with אם לא + FUTURE; don’t drop into the present ממהר.
• אם שתלמד, תצליח -> אם תלמד, תצליח (im tilmad) - אם attaches straight to the verb-clause and takes no ש (unlike במקרה ש / מפני ש).
• במקרא שתאחר -> במקרה שתאחר (bemikre she-te’acher) - “case” is מקרה with ה; מקרא (mikra, with א) means “Scripture / reading” — a wrong letter, a different word.

Tips

• The one reflex to drill: after אם, put a still-to-come event in the FUTURE. אם תבוא, אם ירד, אם תלמד — never the present, however much English pushes you there.
• אם = “if” (you don’t know whether it’ll happen); כש־ = “when” (you’re sure it will). Swapping them flips the sentence between possibility and certainty.
• The result half is flexible: a prediction (future — נישאר בבית), an instruction (imperative / 2nd-person future — תתקשר אליי, בוא), or, for a timeless rule, the present (אם אין חשמל, המקרר לא עובד).
• אז (“then”) is an optional bridge into the result, natural in speech (אם תרצה, אז נדבר). You can always leave it out.
• “If … not / unless” is just אם לא + future: אם לא תמהר… Keep the future after לא, not the present.
• במקרה ש־ (“in case”) is a handy near-synonym for a precaution — but it needs ש, whereas bare אם does not.
• A genuinely present state can stay present after אם (אם אתה עייף, לך לישון — “if you’re tired [right now], go to sleep”); the future rule is only for events that haven’t happened yet.
• For the unreal “if” (would-have / were-to), don’t use אם alone — that’s the לו / אילו + past construction of the counterfactual lesson.