Fill in the blanks with appropriate article /preposition

He is_____ university student.

Fill in the gaps with appropriate Preposition:

We must guard ........ our mistakes.

Fill in the blanks:

I am ashamed _____ his conduct

Translate into English:

আমি তোমার চিঠি পেয়েছি।

Fill in the blanks using appropriate word.

This is ... unique opportunity.

Translate into English:

সে কি স্কুলে যাচ্ছে না?