Read the following paragraph and

Read the following paragraph and underline the topic sentences.
We had a short spring this year. The weather was cold though March and into April due to storms moving down from Canada.There was still snow on the mountains in late April, although it was usually gone by the end of March. We had only two nice weeks in May with the temperatures in the low 70s. But by mid-May, temperatures were in the 90s, and it was hot from then on.
【正确答案】：We had a short spring this year.
【题目解析】：p139