Good Riddles

Question: What can you touch but not see?

Question: A man in a wheelchair is being pushed across a hallway by his wife. When they get to the end of the hallway the man says: stop pushing me. His wife asks why, and the man gets up and starts walking. How did the man get up and start walking if he was in a wheelchair?

Question: What can be stolen legally, it is not illegal to steal it?

Question: What are the next 3 words in the sequence: j,f,m,a,m,j,j,a,s_,_, and _?

Question: There is a man who works on Big Bentley and he keeps the clock running smoothly. One day the clock stops all together, he muttered to himself "It's going to take me all day to fix it!" and he grumbles while he works because he doesn't want to have to change the time, but he finishes by tea and he doesn't have to change the clock by even a minute. How?