一个英语句子不知道对不对，大家帮忙看看！

Question

是：Only when you learn in a fun way （will you） want to keep on doing it

还是：Only when you learn in a fun way （you will） want to keep on doing it
对？

Answer 1

Only when you learn in a fun way （will you） want to keep on doing it
这一句对
这是Only前置的倒装句，情态动态要提前

Answer 2

Only when you learn in a fun way （will you） want to keep on doing it

Answer 3

第一句对。这是倒装句.

Answer 4

是：Only when you learn in a fun way （will you） want to keep on doing it

Only前置倒装，情态动态提前