Only the foolish can disobey the true importance of English. (Interrogative) (Change the sentence)

English is not a native language. (Affirmative) = English is a foreign language. 

Without learning English we cannot hope to get any good job. (Complex) = If we do not learn English, we cannot hope to get any good job. 

The man who knows English well, can go abroad. (Simple) = The man knowing English well can go abroad. 

He becomes a very valuable person. (Exclamatory) = What a valuable person he becomes! 

You must learn English. (Negative) = You cannot but learn English. 

Everybody knows this truth. (Imperative) = Let everybody know this truth.