에러가 반복되서 나타납니다.

 INFO  Starting development server...
98% after emitting CopyPlugin

 ERROR  Failed to compile with 47 errors                                                                                                                 오후 5:01:11

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'computed' was not found in 'vue'

~~~~~~~~~~~~~~~~~

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'defineComponent' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

~~~~~~~~~~~~~~~~~~~~~~~~~~

"export 'h' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'h' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'inject' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

~~~~~~~~~~~~~~~~~~
"export 'nextTick' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'onActivated' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'onDeactivated' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'onUnmounted' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'provide' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'provide' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'provide' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'reactive' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'reactive' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'ref' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'shallowRef' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'unref' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

~~~~~~~~~~~~~~~~~~
"export 'watch' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'watch' was not found in 'vue'

 error  in ./node_modules/vue-router/dist/vue-router.mjs

"export 'watchEffect' was not found in 'vue'