Simplify the following text for a Grade 7 native English-speaking person.
Original: By the early 1930s , however , the increasing speeds began to make the track increasingly dangerous , and in the period 1931 â `` 1935 there were 15 fatalities .
Simplified: By the early 1930s , the increasing speeds began to make the track more dangerous . In the period 1931 â `` 1935 there were 15 fatalities .