Here I will confine myself to only explaining the third sentence 可謂失之遠矣 being translated to modern language will be like 可以說差得很遠了 謂：說 之：pronoun, representing for something unspecified here. If I try to put this word into translation it would be like 可以說（離 something, need to be specified here）差得很遠了

Have you heard the English sentence 'your guess is as good as mine?' 這應該是一首古詩的內容 就算整個寫出來我可能都不一定懂 可谓失之远矣...應該是事實差很多的意思