未知题型 __________ as it was at such a time, his work attracted much attention.A) Being published B) PublishedC) Publishing D) To be published

未知题型 ___________ the earth to be flat, many feared that Columbus would fall off the edge of the earth.A) Having believed B) Believing C) Believed D) Being believed

未知题型 I have kept that portrait ____________ I can see it every day, as it always reminds me of my university days in London.A) which B) whereC) whether D) when