Fall flat and Run aground

Fall flat verb - Fail utterly; collapse.

Run aground and fall flat are semantically related in fail topic. In some cases you can use "Run aground" instead a verb phrase "Fall flat", when it comes to topics like be unsuccessful, fail to attain goal.

Run aground verb - Bring to the ground.

Fall flat and run aground are semantically related in be unsuccessful topic. You can use "Fall flat" instead a verb phrase "Run aground", if it concerns topics such as fail to attain goal.