Invention can be ________ as it may suddenly begin just by noticing something usual.
30. – Why does the boss look worded? – Tom left the company a month ago and his work unfinished ever since.
29. I have been absent for nearly half a month. I can't afford ________ week.
28. The officer was very concerned ________ the latest development in the case because he was concerned ________ it.
27. If we ________ to him, he will make further demands.
26. Parents always tell us not to stay ________ there is danger.