He is so weak that he cannot walk. (Simple )
A
He is so weak that walk
B
He is weak to walk
C
He is too weak to walk
D
He is very weak to walk
Correct Answer: He is too weak to walk
So.... That দিয়ে Complex sentence থাকলে তা simple করার জন্য নিয়ম হচ্ছে - So এর স্থলে Too এবং That এর স্থলে to ব্যবহৃত হয়।