Good afternoon

I was wondering about the answers in the final questions.

The first question says

It is difficult for teachers to make transition from controlled writing activities to free writing activities.
I thought it is difficult for students as in the lecture but why is it also difficult for teacher to help them?
I believed in the lecture you mentioned that we can help them throughout oral prep, clear instruction, and give them a model text.
We can do that throughout carefully planning them. There many resources for them, so I couldn't understand why it is challenging. 

The other question says,

Vocabularies and structures only presented in the presentation stage.
I do understand they should be explain in detail, however, I believed you have explained in a video that they can be expand on to the other stages.
I do agree we should spend time on them, but that does not mean they can "only" be explained in the presentation stage.
This seems like the students can not learn new vocabularies and structures throughout the other activities. 
You can introduce new words through different activities. Also in the lecture you says that you don't have to include the all of the stages in a lesson.

Please guide me a way to find an answer for this question.