US /hʌm əˈlɔŋ/
・UK /hʌm əˈlɒŋ/
This meant that when the factories started humming, there were plenty of workers to hum along with them, especially child laborers.
there were plenty of workers to hum along with them.
and all of a sudden, she started to hum along.
and all of a sudden, she started to hum along.