答案是
【had to...because of】
【from...to】
【The more,the healthier】
因为糟糕的天气,我们不得不呆在家里.
We _____ _____ stay at home _____ _____ the terrible weather.
我们要建一条从北京到天津的新铁路.
We are going to build a new railway _____ Beijing _____ Tianjin.
你越锻炼,就会越健康.
______ _____ exercise you take, ______ ______ you will be.