患生忧，忧生治（魏源）

Problems cause concern and concern for problems will lead to solution.(Wei Yuan)(在魏源看来，“天下之生久矣，一治一乱”，认为其原因是由于“治久习安，安生乱；乱久习患，患生忧，忧生治”。似乎历史就是这样循环往复地演变)

• enable
• encase
• encounter
• encourage
• encouragement
• encouraging
• encouragingly
• end
• endanger
• endangered
• endangered animals
• endangered language
• ending
• endless
• endlessly
• end to
• end up
• end up with
• enemy
• energetic
• energetically
• energise
• energize
• energized
• energy