Let's get together next week to flush out the details

Change 'flush out' to 'flesh out'

Explanation:

Flesh out may sound weird if you've never heard of it before, but it's an actual word (phrase)! Flesh out means to make an object fuller. In this scenario it would mean to basically get all the completed details. Flush out means to cause to leave a hiding place.

quite an interesting way to teach topic sentences, because the answer to this question is the best definition of a topic sentence that one can present, it is as if answering the questions taught you how to do it, this is some real teaching, it is terribly well-done.

the topic sentence in this paragraph is:

topic sentences writers stay on track and keep a paragraph from becoming an aimless collection of sentences about an idea.

which incidentally tells you what a topic sentence should be.