Onahotday,manypeopleliketogotothebeach.Somebeaches,howe...
问题详情：Onahotday,manypeopleliketogotothebeach.Somebeaches,however,arenotsafeforswimming.Atsomebeaches,therearesharksinthewater.Sopeopleputoutsharknets.Theyhelpstoptoomanysharksfromgettingclosetothebe...