### Chinese: 美国海军舰队中14艘“雷鸣潜艇”的行踪通常是被严格保密的。
### English: The whereabouts of 14"Thunder submarines" in the US Navy fleet are usually closely guarded.
### Errors: There is a minor error at "14"Thunder submarines"". There is a major error at "y". There is a major error at "guard".

### Improved English: The whereabouts of the 14 “Boomer Submarines” in the US Navy fleet are usually strictly confidential.