1. Mrs Harris, the owner of three rented houses in Extown, asks her next-door neighbour, Ted, to collect rent from the tenants for her while she is abroad on business. Ted collects the rents and when Mrs Harris returns she says to him, 'I'll give you £50 for your work.'

Can Ted enforce the promise?

2. John, a plumber, installs a new bathroom for Mr and Mrs Bolton for an agreed price of £500. Five weeks after sending the bill John still has not received payment. He rings the Boltons and speaks to Mrs Bolton. She says that she is unhappy about the quality of John's work, which she claims is only worth £350 at most. She also tells John that her husband has just lost his job and they can only afford to pay £100. John reluctantly agrees to accept a cheque for this amount 'in full settlement'.

Three months later John hears that Mr Bolton is back in employment and he wonders whether he can recover the outstanding money.