改错题I went through the test for many times but i could only answer... ...

"went through" 通过 为瞬时性的
for 加时间段

I have gone through the test for many times but i could only answer... ...
我试了很多次，但我还是只能说……

I went through the test （for） many times but i could only answer... ...

把for去了

I have viewed the exam paper many times. Eventualy, there is only 1 question I can answered.

for 后面跟的是一个时间段