Fill in each blank with a suitab

Fill in each blank with a suitable word given below.
by   in   grinding   explained   with   out   published   since   and   occurred
For centuries people have observed strange phenomena before large earthquakes, such as light coming from ridges 31mountaintops. These reports were once dismissed by many scientists,32 part because they are often entangled in unscientific theories. For example, some who reported the lights thought they were produced 33 UFOs. But the lights are not necessarily created by E.T. "Earthquake lights are a real phenomenon- they're not UFOs," researcher Robert Theriault told Nature. "They can be scientifically 34." In study35in the January/February issue of i the journal Seismological Research Letters, Theriault and colleagues pulled together reliable sightings of these lights36 1600, and found some strange similarities. A total of 6337 of the 65 sightings38 along nearly vertical faults. The researchers suggest that along these faults, the stress of rocks39 against each other produces electrical charges, which can travel upward and interact40the atmosphere to create light.
回答第（32）空
【正确答案】：in