### Chinese: 这是美国弹道导弹潜艇自2016年以来首次访问关岛，也是自20世纪80年代以来第二次公开访问关岛。
### English: This is the first U.S. ballistic missile submarine to visit Guam since 2016, and the second public visit to Guam since the 1980s.
### Errors: There is no error in the English translation.

### Improved English: This is the first visit to Guam by a US ballistic missile submarine since 2016 and the second public visit to Guam since the 1980s.
