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'
와 같이 나타납니다. ~~~ 된거는 4번이상 동일 메시지가 반복된겁니다 .체크 부탁드립니다...ㅠㅠ
크론 받은거에서 도 일단 npm run serve가 되지 않았습니다.

인프런 커뮤니티 질문&답변