Errors, "haven't closed the table properly"

wp_users: 2 clients are using or haven’t closed the table properly
wp_usermeta: 2 clients are using or haven’t closed the table properly
wp_posts: 3 clients are using or haven’t closed the table properly
wp_comments: 3 clients are using or haven’t closed the table properly
wp_options: Table is marked as crashed
wp_postmeta: 3 clients are using or haven’t closed the table properly
wp_term_taxonomy: 3 clients are using or haven’t closed the table properly
wp_term_relationships: 3 clients are using or haven’t closed the table properly
wp_commentmeta: 3 clients are using or haven’t closed the table properly

No idea what does means or how to fix. please help.