Hamish Robert is going to have coffee
Robert is going to wash up  after breakfast 
Robert is going to do his room
Jim is going to take a shower
Jim is going to help his brother in the kitchen
Jim is going to drive to the airport
R and J are going to do Glasgow
R and J are going to visit glasgow museums
R and J are going to come to London
Итак, IS  используется  для обозначение единственного числа (Джим IS, Роберт IS)
ARE - множественное (Джим и Роберт ARE)
При чем это относится и к предметам.