This sounds like you are reading a quote from a dictionary. Hold their feet to the fire LOL.
The official opposition in Canada, in a majority Government situation, has no power accept the power of complaint. All members of each party are expected to vote the party line on all issues, ignoring the wishes of the constituents they represent. When we vote in an MP we hope they represent the majority of the values of the people in our electoral region. In Canada there are no true checks and balances in the Government. Unlike the US who has an elected Senate that have a veto on all bills, an elected house of representatives who hold a veto and an elected leader, the president, who also has a veto.
In Canada we vote in a party who have appointed a leader and in a majority situation the country is at their mercy for the duration. While our Senate has the power to veto a bill that power is seldom exercised. Our Senate is little more than a retirement home for people who have served their party well in the past. In effect we have an elected dictatorship so we must be very sure of the people we elect.