The bedford say using the active voice unless I have a good reason for choosing the passive, but I heard someone say using passive in my composition can make me getting a higher score. It is exactly the opposite compare bedford's rules, so I don't know should I use passive sentence in IELTS test.

As for the parallel ideas, I would say I didn't notice that when I wrote something before. Now I know that it is better to make ideas paralleled when I use a conjunction.

In one word, bedford help me a lot this week. I hope things could be much better in the future.