How to fix these errors and what caused them?

I am trying to repair databases and get these repair errors:

wp_users: 1 client is using or hasn’t closed the table properly
wp_usermeta: 10 clients are using or haven’t closed the table properly
wp_comments: 1 client is using or hasn’t closed the table properly
wp_options: Table is marked as crashed
wp_postmeta: 18 clients are using or haven’t closed the table properly
wp_terms: 1 client is using or hasn’t closed the table properly
wp_term_taxonomy: 2 clients are using or haven’t closed the table properly
wp_term_relationships: 2 clients are using or haven’t closed the table properly