Manifestation is where your thoughts and your energy can create your reality. If you are constantly being negative and feeling down, then you are going to attract and manifest negative energy.
They mostly last for a few weeks, or months, but severe cases can last for years.
The word "I", or me or you, you shouldn't use the word I especially, unless quoting someone exactly...
Answer:
l saw a little boy run across. The car hit the boy. The car stopped and a man came out of the car. The man phoned for an ambulance immediately. The ambulance arrived in no time.