By Mockly English · Last updated:
Interviewers are not grading your accent. They need to follow your reasoning in English. She was a security engineer in United States. The gap was system design — not the technical content.
At a glance
| Role | Security Engineer |
|---|---|
| Location | United States |
| English challenge | system design |
| Interview problem | System Design |
| Target | |
| Preparation | Live mocks with English feedback on the same answers |
| Outcome | Gained clearer, more confident English for interviews |
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Interviewers are not grading your accent. They need to follow your reasoning in English. She was a security engineer in United States. Day-to-day work used Python. The next interviews were at Google, in English. In the room, system design was what broke down.
Practice matched the round she actually had to speak: system design for Google. Each mock got notes on the same answer — where she paused, which words were vague, and where the structure broke.
Useful references along the way: What to expect in English interviews, Pronouncing numbers and metrics.
System design is a 30–45 minute spoken explanation. You must sequence components, defend trade-offs, handle follow-ups, and keep vocabulary accurate while the clock runs. Translating each sentence in your head uses the time the interviewer needed for depth. A fixed spoken order is what keeps the round coherent in a second language.
Preparing for a similar path? Read How a Croatian Security Engineer Prepped for Google's Behavioral Interviews.
Gained clearer, more confident English for interviews. She could explain the work more clearly when questions got hard. That readiness was the goal — not a promised job offer.
She prepared for English-language interviews as a security engineer. The stack was Python. Written English was stronger than speaking under the clock.
Practice this vocabulary drill
Try a locked preview of a tech-vocabulary drill used in this plan — with pronunciation prompts.
Sign up to unlock this exercise →Practise explaining system design in English
No card required. Start with a 7-day free trial — a lesson, a mock interview, or both.
Create your Mockly account →The language of the round you will face — here, system design. Learn full sentences for that format, not a general business-English course.
No. Clarity and structure are the bar. A small accent is fine if they can follow your decisions and numbers.
Practise the real format out loud, especially system design. Get notes on pauses and vague wording after each mock — not only on the technical content.
Many B2+ candidates need several weeks of focused, spoken practice. Weekly mocks beat a last-minute cram.

Mockly’s approach is genuinely personalized — they use a variety of methods tailored to your specific needs. With their help, I improved my spoken English and prepared thoroughly for behavioral interview questions across different companies. This not only helped me refine my stories grammatically but also ensured I was using the right examples to answer specific questions effectively.

I’ve had the pleasure of practicing English with Mockly and I truly appreciate the progress I’ve made. I highly recommend their services to professionals in tech and beyond. I particularly enjoy the teaching style and the philosophy behind it: “If you enjoy the process, you’ll get it.” The personalized learning plans make every session practical and useful. Their hands-on knowledge and genuine interest in the world of technology will genuinely boost your English skills.
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Case studies are illustrative, based on patterns from real coaching sessions.