It is…that…是三个不同的句式

1. 强调句式

例：It is your encouragement that helped me out of the hard times. 是你的鼓励帮助我走出了那些艰难时刻。

2. 形式主语+that从句

例：It is true that your encouragement helped me out of the hard times. 真的是你的鼓励帮助我走出了那些艰难时刻。