It's impossible to read an interviewer's mind – and while you can't predict their list of questions or how they will evaluate you, there are common interview traps you should be ready for.

The secret to acing job interviews lies in confidence and preparation. "You have to play detective and figure out your shortcomings, or the challenges you'll face in the role you've applied for," Jeff Hyman, an executive recruiter of 25 years, tells CNBC Make It. "The wrong time to think about this is during the interview, because then you're frazzled."

Throughout his career Hyman, who is also the CEO of Recruit Rockstars, an executive search firm, has interviewed more than 30,000 candidates, and there are three questions that consistently stump people.

Here's which questions to watch out for, and how to respond to them.

'So, tell me about yourself'

Interviewers tend to start conversations with this question as an icebreaker, but it can often fluster job candidates and lead to "long, rambling answers" that waste time, Hyman says. 

Instead, keep your response short (ideally under one minute) and highlight your strengths and accomplishments. "With this question, hiring managers are really asking, 'Why are you sitting in front of me today? If you're so good, why are you looking for a job?'" Hyman explains. 

The best approach for answering this question is explaining not just what you've done, but why: what motivates you and how you want to make a difference in your next role.

'What's your biggest accomplishment?'

Job candidates often make two mistakes when answering this question, Hyman says. They are either too humble in their response, and can't articulate the impact they've made at work, or they can't quantify that impact with numbers. 

"It's an important question to be ready for, but a lot of people bomb it," he says. 

Pick the biggest achievement of your career, whether it's beating a sales target, giving a great presentation or organizing a big event, and briefly explain the steps you took to get there.

Then make sure you mention numbers to explain the impact your accomplishment had on the business: "I grew sales by X%" or "I increased customer satisfaction by Y," for example.

'Can you explain this gap in your resume?'

If you recently lost or left your job, you might be dreading this interview question. "A lot of candidates are ashamed or embarrassed by a resume gap and think they're the only person over the past two years that's experienced massive life changes," Hyman says.

But the ongoing coronavirus pandemic has upended many lives, and hiring managers are more empathetic to resume gaps than you might think, Hyman notes. It's important to answer the question truthfully, directly and unapologetically. 

"Be vulnerable and briefly explain why you took 3 months, 6 months, or a year to care for your ill parent, travel to Europe or however you spent your time," Hyman says. "End on a positive note and highlight what you learned from the experience."

Check out:

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