I have been keeping the portrait _____ I can see it every day, as it always reminds me of my childhood in Paris.
| A．since | B．where | C．as | D．if |
This problem may lead to more serious ones if _____ unsolved.
| A．left | B．keeping | C．remained | D．making |
What a fast learner he was! He_____ a lot of French when he lived with the native.
| A．took up | B．made up | C．picked up | D．turned up |
—Does John serve in the army?
—No, but he________in the army for 8 years.
| A．would serve | B．has served | C．is serving | D．served |
He was working on a new book ________ I went to see him.
| A．first time | B．for the first time |
| C．by the first time | D．the first time |
Not until the motorbike looked almost new repairing and cleaning it.
| A．he stopped | B．did he stop |
| C．stopped he | D．he did stop |