Use <nav> for any element that represents the navigation within the page and the site: menu or navbar.
Article can be a complete news story, but also a forum post, comment, or sidebar widget. It needs a unique heading.
Anything on a sidebar, the comments, footnotes, glossary, advertisement, should get the <aside> tag.
An image, an ensemble of image, a graphic... comes with a <figcaption> element for the legend.
If it has a title but is not an <article>, then it should be a <section>. There can be multiple <section> tags in an <article>.
Probably a paragraph. Or another appropriate element such as <address>, <blockquote>, <pre>...
Stands for "division of page".
The default block in the flow, which doesn’t have any particular meaning.