单项选择题
A．There are a lot of boxes in the way. B．The boxes might be too heavy for her to lift. C．He is tired after lifting the boxes. D．He eann0t lift the heavy boxes.
A. $300. B. $450. C. $500. D. $600.
A．Building and selling TV sets. B．Making TV sets and repairing them. C．Building, repairing and selling things. D．Persuading people to buy newspapers.