• Complete sentence: The safety of the workers is the main concern of the management.
- Bangla Meaning: কর্মীদের নিরাপত্তাই ব্যবস্থাপনা কর্তৃপক্ষের প্রধান উদ্বেগের বিষয়।

• Concern of (someone)
- English Meaning: something that involves or affects you or is important to you
- Bangla Meaning: কোনো বিষয় যাতে কেউ উৎসাহী বা যা কারো কাছে গুরুত্বপূর্ণ; উদ্বেগ।

• More examples:
- What were the major concerns of the writers from this period?
- I don't want to hear about it - it's no concern of mine!

• অন্যদিকে,
• Concerned for (someone/something):
- English Meaning: a worried or nervous feeling about something, or something that makes you feel worried.
- Bangla Meaning: কোন কিছুর জন্য উদ্বিগ্ন হওয়া।
- যেমন: Concern for the safety of the two missing teenagers is growing.

• Concerned in:
- English Meaning: involved in something.
- Bangla Meaning: কোন কিছুতে জড়িত থাকা।

• Concerned about/over:
- English Meaning: a worried or nervous feeling about something.
- Bangla Meaning: কোন কিছু সম্পর্কে উদ্বিগ্ন হওয়া।
- যেমন: There's a lot of public concern about dangerous toxins recently found in food.

Source:
1. Longman Dictionary.
2. Cambridge Dictionary.
3. Merriam-Webster Dictionary.