Cloning an animal is a complex ________ that can go fatally wrong at any stage.
| A．process | B．regulation | C．step | D．method |
________for a long time，but he tried his best to make up for what he missed.
| A．Being ill staying in hospital |
| B．Having been ill staying in hospital |
| C．He was ill staying in hospital |
| D．To be ill staying in hospital |
________ from heart trouble for years，Professor White has to take some medicine with him wherever he goes.
| A．Suffered | B．Suffering | C．Having suffered | D．Being suffered |
Did you ask whose computer________？
| A．this blue one was | B．is this blue one |
| C．it was this blue one | D．this blue one is |
—Do you think it’s going to rain over the weekend?
—________.
| A．I don’t believe | B．I don’t believe it |
| C．I believe not so | D．I believe not |
Johnson had made up his mind to give it up，but on________ second thought he determined to try________ third time.
| A．/；a | B．/；/ | C．a；a | D．the；a |