i'd appreciate ____ if you could lend me a hand with my homework.1.so 2.it 3.that 4.you为什么选2

i'd appreciate ____ if you could lend me a hand with my homework.1.so 2.it 3.that 4.you为什么选2
i'd appreciate ____ if you could lend me a hand with my homework.
1.so 2.it 3.that 4.you
为什么选2

i'd appreciate ____ if you could lend me a hand with my homework.1.so 2.it 3.that 4.you为什么选2
2 it代表you lend me a hand with my homework

IT是代主语!

固定句型,貔似如此