Ellen was a painter of birds and of nature, _____, for some reason, had withdrawn from all human society.
________,John returned to school from his hometown.
—We didn’t find the Blacks ________ the lecture. —No one had told them about ________ a lecture the following day.
His first book ________ next month is based on a true story.
In order to improve English,________.
The global warming is more and more serious,for which human beings ________.