Read the following paragraph and underline the topic sentences.C

Read the following paragraph and underline the topic sentences.
Cooking in a microwave oven has simplified by hectic life. Instead of having to wait the interminable ten minutes for my morning coffee, I can place my cup in the micro and have hot coffee in seconds. I no longer have to decide in the foggy morning what ingredients must be defrosted for the evening meal. I can now come home at 5 p.m., decide what I feel like eating, and have it defrosted in a master of minutes. The shortened cooking time means I can have full course meals that once took me hours to cook. The microwave also makes clean-up much easier because the dish I cook in is the dish I eat in. Since I have a microwave oven, it saves me a lot of time and gives me much help.
【正确答案】：Cooking in a microwave oven has simplified by hectic life.
【题目解析】：p161