That Thing You Do Mid-Sentence
You’re talking to your mom in Farsi. Everything’s going fine. Then you hit a word you don’t know. or a concept that feels easier in English. and out it comes: “Man really frustrate shodam.” Or “It’s so weird, nemidoonam how to explain it.” Half Persian, half English, fully annoying to you.
This guide is part of our Heritage Persian Guide series.
Farsi code switching is what linguists call this. And if you’re a diaspora Iranian, you do it constantly. Maybe you’ve accepted it. Maybe it drives you crazy. Maybe your relatives in Iran have pointed it out. gently or not so gently. and you felt that familiar sting of not being “Iranian enough.”
Here’s what I want you to know upfront: code switching is natural. Every bilingual person on earth does it. It’s not laziness, it’s not stupidity, and it’s not a sign that your Farsi is broken. But. and this is the part people skip. when you can’t turn it off, that tells you something specific about where your Persian has gaps.
This post is about understanding those gaps and filling them.
Why You Mix English Into Your Farsi
There are a few distinct reasons, and they’re worth separating because each one has a different fix.
Missing vocabulary. This is the big one. You literally don’t know the Persian word for what you’re trying to say. Abstract concepts are the usual culprits: “boundaries” (marzeha / مرزها, though in the emotional sense Persians might say khat-e ghermez / خط قرمز), “toxic” (sammi / سمّی, but nobody in casual Farsi says that. they’d say “adam-e mozakhraf” / آدم مزخرف), “anxiety” (ezterab / اضطراب). You know these ideas in English because you went to school in English, thought in English, processed your emotions in English. The Persian equivalents simply weren’t part of your input.
Emotional expression defaults. When you’re angry, excited, sad, or stressed, you revert to your dominant language. the one where feelings were first labeled for you. For most diaspora kids, that’s English. So “I’m so khasteam” (I’m so tired-I am) comes out instead of “kheili khasteh-am” (خیلی خستهام), because the emotional impulse fires in English first and the Farsi verb ending gets tacked on like an afterthought.
Social habit. If everyone in your Iranian-American (or Iranian-British, or Iranian-Canadian) friend group code-switches, it becomes the default register of your social circle. It’s not about ability at that point. it’s about belonging. Switching to pure Farsi in a group that always mixes would feel performative and weird.
Speed and cognitive load. Pure Farsi requires more processing power for you than English does. When you’re tired, distracted, or in a fast-moving conversation, your brain takes shortcuts. English words are the shortcut.
When Code Switching Actually Matters
I’m not going to tell you to stop code switching entirely. Among bilingual friends who all do it? It’s fine. It’s a legitimate way of communicating. Linguists have studied this. code switching follows grammatical rules, it’s creative, it’s a feature of bilingual communities worldwide.
But there are situations where it matters:
Talking to monolingual relatives. Your khaleh (خاله) in Tehran doesn’t know what “boundaries” means. When you switch to English mid-sentence with her, communication breaks down. She might smile and nod, but she didn’t understand you. Or worse. she understood that you couldn’t say it in Farsi, and that creates a distance between you.
Professional or formal contexts. If you ever work with Iranian clients, attend a Persian cultural event, or find yourself in any situation where pure Farsi is expected, code switching marks you immediately as “not from Iran.” That’s not inherently bad, but it limits you.
Your own sense of identity. This one’s personal. A lot of diaspora kids I teach come to me because they’re tired of feeling like they can’t fully express themselves in their parents’ language. They can do 70% in Farsi, and that last 30%. the abstract stuff, the emotional stuff, the stuff that makes you you. always comes out in English. That gap bothers them. It should. Not because it’s shameful, but because it’s fixable.
The Most Common Switches (And Their Farsi Alternatives)
Let me give you real examples. These are things I hear from students every week.
“I’m so stress-am” → Man kheili estres daaram (من خیلی استرس دارم). Or better: asabi-am (عصبیام) if you mean generally stressed, or negaran-am (نگرانم) if it’s more like worry.
“It’s so awkward” → Kheili zahmat-e (خیلی زحمته), or kheili odd-e… no wait, that’s English too. Try: kheili ma’zerat-aavar-e (خیلی معذرتآوره) for socially awkward situations, or just kheili bad-e (خیلی بده) for “it’s really bad/uncomfortable.”
“Midooni what I mean?” → Manzeram-o migiri? (منظرمو میگیری؟). literally “do you catch my meaning?” This is casual Tehrani and perfectly natural. I talk more about these spoken forms in my breakdown of spoken versus written Persian.
“That’s so random” → This one’s hard because “random” as slang doesn’t have a clean Farsi equivalent. You could say “bi rabt” (بیربط) meaning “unrelated” or “ajib-gharib” (عجیبغریب) meaning “strange.” Neither is a perfect match, and that’s okay. not every English concept maps neatly onto Farsi.
“I need to set boundaries” → Baayad khat-e ghermez-am-o moshakhkhas konam (باید خط قرمزمو مشخص کنم). Literally: “I need to make my red lines clear.” Persian uses “red line” where English uses “boundary” in the emotional sense.
“I literally can’t” → Vaghe’an nemitonam (واقعاً نمیتونم). Simple. You probably already know this one but reach for “literally” out of English habit.
How to Build the Missing Vocabulary
The fix isn’t complicated, but it requires consistency. Here’s what works.
The Gap Journal. Carry a note on your phone. Every time you switch to English mid-Farsi because you don’t know a word, write that word down. Don’t look it up in the moment. just log it. At the end of the week, you’ll have a personalized list of your exact gaps. Then look them all up, make flashcards, and drill them. I explain the full flashcard system in my Anki for Persian guide. it’s the fastest way to make new vocabulary stick.
Consume Persian media in your gap areas. If you always switch to English when talking about emotions, listen to Persian podcasts about relationships or psychology. If you switch when talking about work, find Persian content about business. Your brain needs to hear these concepts expressed in Farsi before it can produce them in Farsi. BBC Persian’s YouTube channel is free and covers everything from politics to culture.
Practice with a real person who’ll push you. You need someone who will stop you when you switch and ask “how would you say that in Farsi?” Not in an annoying way. in a supportive, let’s-figure-this-out way. This is genuinely one of the most effective things I do in lessons. Heritage speakers often know more than they think; they just need someone to pull it out of them. If you want to try this, book a session with me on Preply and we’ll map your specific gaps.
Shadow Iranian speakers. Pick a Persian YouTuber or podcaster you like. Listen to a sentence, pause, repeat it exactly. This trains your brain to produce full Persian sentences without English inserts. It also helps with the rhythm and flow of natural Farsi. something you might have in your ear but not in your mouth.
The 5-minute pure Farsi challenge. Set a timer. Talk to yourself (or a willing family member) for five minutes in only Farsi. No English at all. When you hit a word you don’t know, describe it in Farsi instead of switching. “That thing when you feel bad about something you did” instead of “guilt.” This is frustrating at first and incredibly effective over time. It forces your brain to find Persian pathways instead of defaulting to English.
The Words You Think Don’t Exist in Farsi (But Do)
A common belief among diaspora kids: “Farsi just doesn’t have a word for that.” Sometimes it’s true. languages have genuine gaps. But most of the time, the word exists. You just never learned it.
Persian is an old, rich language with vocabulary for concepts you’d never expect. “Procrastination”. ta’lal (تعلل). “Passive-aggressive”. this one genuinely doesn’t have a single-word equivalent, but Persians describe it as “zir-e aabi kaar kardan” (زیر آبی کار کردن) or “poshteh sar harf zadan” (پشت سر حرف زدن). “Vibe”. haales-o-havaa (حال و هوا). “Cringe”. this is newer slang and even Iranians in Iran sometimes just say “cringe” now.
Language evolves. Persian has absorbed words from Arabic, French, Turkish, and yes, English throughout its history. Some English loanwords are now standard in Iranian Persian. “stress” (استرس), “depression” (دپرشن in casual speech), “feedback” (فیدبک). Using those isn’t code switching; it’s just modern Persian.
The trick is knowing the difference between an accepted loanword and a gap in your vocabulary. “Stress” in Farsi? Loanword, everyone uses it. “I need to process my emotions” in half English? That’s a gap. For a broader look at how casual Persian actually works versus the textbook version, check out these essential Farsi slang terms.
Stop Feeling Guilty About It
One more thing. The guilt that comes with code switching. the feeling that you’re failing your culture, disappointing your parents, losing your heritage. that guilt is unproductive. I’ve watched students freeze up because they’re so afraid of switching to English that they stop talking altogether. That’s worse.
Code switching is where you are right now. It’s a data point, not a verdict. Every English word you insert into your Farsi is a signpost pointing to a specific vocabulary gap. Treat it that way. clinically, practically. and you’ll improve fast.
The goal isn’t to never use English again when speaking Farsi. The goal is to have the choice. To be able to turn it off when you want to, when the situation calls for it, when you’re sitting across from your grandmother and want to tell her something real without reaching for English halfway through.
That ability is buildable. And it’s closer than you think. because you’re not starting from zero. You’re starting from a childhood of hearing Persian every day. That’s a foundation most language learners would kill for.
If you want a structured way to fill those gaps. vocabulary drills that target exactly the domains heritage speakers are missing. ZabanYar lets you skip the beginner stuff and focus on building active production.
For a deeper look at the heritage speaker path and what comes next, keep an eye on the heritage Farsi learner hub. I’m building it specifically for people in your situation.
Keep Learning
This guide is part of: Heritage Persian Guide
Read next: Your Farsi Accent · The Fingilish Trap
New to Farsi? Start with the complete beginner’s guide.