Do they have the difference in the sense between this two sentences ? Was it not obvious? Wasn't it obvious?

Can I say so? He might be able to improve the situation

Which sentence sounds more naturally? Why should we spend so much money on it ? Why should we spend on it so much money?

Do these sentences have the same sense? Our father thinks so, too Our father also thinks so

Which sentence do sound more naturally?(or both incorrect) How long does one English lesson last? How long is one English lesson?

What is the difference? what newspapers are interested to you? what newspapers are interesting for you?

Which one is more correct or both incorrect? Did he develop doing the same things again and again? Was he developing doing the same things again and again?

Which one is more correct or both incorrect? whose mother does cook breakfast? whose mother is cooking breakfast?

which one is correct ? Who are we waiting for? Who are we waiting ?