$1$. If there aren't any tickets left when we reach the front of the queue, we will have waited all the time for nothing.
$2$. I haven't decided yet about whether to buy a new car or second hand one. But I am thinking about it
$3$. There are any errors, let me know.
$4$. We have just got to the top in time.The sun will rise in a minute.
$5$. By midnight he will have been unconscious for forty-eight hours.
$6$. It can't have been Anna who cooked that food.She was out all day yesterday.
$7$. It is highly desirable that from every product in regular production, samples are withdrawn periodically.
$8$. The portrait is widely known to have been painted by an Italian.
$9$. Can you keep calm for a moment? You are always making noise in class
$10$. You visited Aunt Mary while you were in Paris.