Question

If+they+want+answers+___+all+their+questions+about+science空填什么

Answer 1

问：If+they+want+answers+___+all+their+questions+about+science空填什么

答：If they want answers to all their questions about science.

问：为什么要用to

答：在这个句子中，“to”是一个介词，用来引导一个不定式短语作为目的状语。表示他们想要获得关于科学的答案，这是他们的目的。因此，正确的句子应该是：“If they want answers to all their questions about science。”