Reading in the Baseiment

Question: A woman was reading in the basement when her husband, thinking the basement was empty, turned off the light. The woman continued reading. There were no lamps or flashlights and the light her husband turned off didn't come back on. How was the woman able to read?

Question: People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?

Question: During what month do people sleep the least?

Question: When is 99 more than 100?

Question: What can be broken but never forgotten?

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?