All the orders were given by word of mouth so that no written evidence could be discovered later.所有命令都是口头传达的，所以事后找不到任何书面证据。She backed her argument up with written evidence. = Written evidence backed her argument up.她用书面证据来支持自己的论点。She backed her argument with written evidence.她为自己的论点提供了书面证据。