Mentoring junior developers is one of the most valuable things a tech lead does. But if your team operates in English, the way you communicate matters as much as what you say. The right words can unlock a junior dev’s potential. The wrong words — even well-intentioned — can shut someone down.
This guide gives you the exact English phrases, vocabulary, and practice scripts to mentor confidently as a Vietnamese tech lead in an international environment.
Why Mentoring in English Feels Hard
When we mentor in Vietnamese, tone does a lot of the work. A soft “em thử nghĩ lại xem” can be gentle without sounding weak. In English, it’s easy to sound too blunt (“That’s wrong”) or too vague (“It could be better maybe”).
The goal: be direct without being harsh, and encouraging without being dishonest.
🗣️ Key Phrases to Say Out Loud
Practice these out loud — say them slowly, then at normal speed:
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“What was your thinking here?” — /wɒt wəz jɔː ˈθɪŋkɪŋ hɪə/ Opens a conversation without making them feel judged.
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“That’s a good starting point — let’s build on it.” — /ðæts ə ɡʊd ˈstɑːtɪŋ pɔɪnt — lets bɪld ɒn ɪt/ Validates effort while signaling there’s more to explore.
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“I’ve seen this pattern cause issues at scale — want me to walk you through why?” — /aɪv siːn ðɪs ˈpætən kɔːz ˈɪʃuːz ət skeɪl — wɒnt miː tə wɔːk juː θruː waɪ/ Teaches from experience, not from ego.
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“What would you do differently if you had to do this again?” — /wɒt wʊd juː duː ˈdɪfrəntli ɪf juː hæd tə duː ðɪs əˈɡen/ Builds self-reflection skills — essential for a senior developer.
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“Let’s time-box this — try it your way for 30 minutes, then let’s sync.” — /lets taɪm bɒks ðɪs — traɪ ɪt jɔː weɪ fər ˈθɜːti ˈmɪnɪts, ðen lets sɪŋk/ Gives autonomy with a safety net.
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“That’s actually a really common mistake — I made it too when I was starting out.” — /ðæts ˈæktʃuəli ə ˈrɪəli ˈkɒmən mɪˈsteɪk — aɪ meɪd ɪt tuː wen aɪ wəz ˈstɑːtɪŋ aʊt/ Normalizes struggle and builds psychological safety.
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“Can you explain this to me like I haven’t seen the codebase?” — /kæn juː ɪkˈspleɪn ðɪs tə miː laɪk aɪ hævnt siːn ðə ˈkəʊdbeɪs/ Tests deep understanding — if they can explain it simply, they understand it.
📚 Vocabulary
| Word / Phrase | Pronunciation | Meaning | Example |
|---|---|---|---|
| scaffold | /ˈskæfəʊld/ | Temporary support structure | ”I’ll scaffold the first feature — you complete the rest.” |
| ownership | /ˈəʊnəʃɪp/ | Taking full responsibility | ”I want you to take ownership of this module.” |
| trade-off | /ˈtreɪd ɒf/ | Balancing competing benefits | ”Walk me through the trade-offs in your design.” |
| rubber duck | /ˈrʌbə dʌk/ | Explaining code out loud to spot bugs | ”Have you tried rubber-ducking this problem?“ |
| unblock | /ʌnˈblɒk/ | Remove an obstacle | ”What do you need from me to unblock yourself?“ |
| iterate | /ˈɪtəreɪt/ | Improve in small steps | ”Don’t try to get it perfect — iterate.” |
| pair | /peə/ | Work together on the same task | ”Let’s pair on this for an hour.” |
🎯 Practice Now
Scenario 1: Junior dev submits a PR with messy code
Junior dev: “I finished the feature. Here’s the PR.”
Your response (choose one level):
- Gentle: “Thanks for pushing this! Before I review it — what do you think could be improved?”
- Direct: “This works, but let’s talk about readability. Can you walk me through your variable naming choices?”
- Coaching: “I see you got it working — great. Now, if you had to hand this to a new team member to maintain, what would worry you?”
Scenario 2: Junior dev is stuck and keeps asking for help
Junior dev: “I don’t know how to fix this bug. Can you help me?”
Your response:
“Tell me what you’ve already tried.” (They explain) “Okay — and what does the error message tell you?” (They say they don’t know) “Let’s read it together. When I see an error, the first thing I look for is… what line it points to, and what word I don’t understand. Walk me through what you see.”
This is the Socratic method — guide them to the answer rather than giving it.
Scenario 3: Junior dev pushes back on your suggestion
Junior dev: “I think my way is fine. Why does it need to change?”
Your response:
“That’s a fair question — I should explain my reasoning. The issue I see is [X]. Have you encountered this before? … No? Let me show you a real example from production where this pattern caused [Y]. Does that change your thinking?”
Key principle: Explain the ‘why’, not just the ‘what’.
⏱️ 5-Minute Drill
Read this script out loud, timing yourself. Aim for clear, confident delivery — not speed.
“Hey [junior’s name], do you have 5 minutes? I wanted to give you some feedback on the PR.
First — the logic is solid. You understood the requirement and got it working. That’s the most important thing.
Now, a couple of things I want us to look at together. The first is this function here — it’s doing three things at once. Can you see them? Right. In general, a function should do one thing. If you have to use ‘and’ when naming it, it’s probably too big.
The second thing is error handling. What happens if the API returns null here? Exactly — it breaks. Let’s think about how to guard against that.
I’m not asking you to fix this right now. I just want you to sit with these two ideas — single responsibility and defensive coding. Next time you write a function, ask yourself: what does this do? And what could go wrong? Okay? Great work today — keep going.”
(Word count check: approximately 820 words)
From My Experience as a Vietnamese Tech Lead
The hardest adjustment when mentoring in English was learning to be comfortable with silence. In Vietnamese mentoring conversations, we often jump in quickly to help. In English-speaking teams — especially Western ones — silence after a question means the junior is thinking, and that’s good.
Ask the question. Wait. Let them struggle a little. That productive struggle is where the real learning happens.
Another thing: “I don’t know” is perfectly acceptable in English professional culture. Saying “That’s a great question — I’d have to look that up” signals honesty and intellectual humility. Teach your juniors this early.
Your role as a tech lead is not to have all the answers. It’s to ask the questions that make others find the answers themselves.