At ____ in the streets,you can see the traffic lights.(cross

At ____ in the streets,you can see the traffic lights.(cross)
In Shanghai,you can find many houses for ___ every where.(sell)
The boys like playing ______ each other.(trick)
Washing machines can save us time ______ housework.(do)
Over 120,000 ____ work in Hongkong.They are from _____ (philipinos)