sketch_jun08a:7: error: 'DHT11' does not name a type

 DHT11 dht11(5);

 ^

C:\Users\USER\Documents\Arduino\sketch_jun08a\sketch_jun08a.ino: In function 'void Sensing()':

sketch_jun08a:89: error: expected primary-expression before '.' token

   if((err=dht11.read(humi, temp))==0)

                ^

exit status 1
'DHT11' does not name a type