He felt very sad that though he worked very indeed, he was not able to jump .
Since nobody gave him any help, he ______ have done the research on his own.
I was wondering what to do with my car which won’t start ______ a kind man offered to help.
---Why does Peter look upset? --- He is a newcomer to the class and is having difficulty ______ by his classmates.
Her question was so difficult that I could hardly make any _______ of it at all.
Human beings are different from animals _____ they can use language as a tool to communicate.