What topics are listed under Dewey decimal system listed for 400-499?

The 400's are for language-associated topics:

• Class 400 - Language
• 400 Language
• • 400 Language
  • 401 Philosophy & theory
  • 402 Miscellany
  • 403 Dictionaries & encyclopedias
  • 404 Special topics
  • 405 Serial publications
  • 406 Organizations & management
  • 407 Education, research, related topics
  • 408 With respect to kinds of persons
  • 409 Geographical & persons treatment
• 410 Linguistics
• • 411 Writing systems
  • 412 Etymology
  • 413 Dictionaries
  • 414 Phonology
  • 415 Structural systems (Grammar)
  • 416 No longer used-formerly Prosody (linguistics)
  • 417 Dialectology & historical linguistics
  • 418 Standard usage; Applied linguistics
  • 419 Verbal language not spoken or written
• 420 English & Old English
• • 421 English writing system & phonology
  • 422 English etymology
  • 423 English dictionaries
  • 424 No longer used-formerly Englishthesauruses
  • 425 English grammar
  • 426 No longer used-formerly English prosodies
  • 427 English language variations
  • 428 Standard English usage
  • 429 Old English (Anglo-Saxon)
• 430 Germanic languages; German
• • 431 German writing system & phonology
  • 432 German etymology
  • 433 German dictionaries
  • 434 Not assigned or no longer used
  • 435 German grammar
  • 436 Not assigned or no longer used
  • 437 German language variations
  • 438 Standard German usage
  • 439 Other Germanic languages
• 440 Romance languages; French
• • 441 French writing system & phonology
  • 442 French etymology
  • 443 French dictionaries
  • 444 Not assigned or no longer used
  • 445 French grammar
  • 446 Not assigned or no longer used
  • 447 French language variations
  • 448 Standard French usage
  • 449 Provençal & Catalan
• 450 Italian, Romanian,Rhaeto-Romanic
• • 451 Italian writing system & phonology
  • 452 Italian etymology
  • 453 Italian dictionaries
  • 454 Not assigned or no longer used
  • 455 Italian grammar
  • 456 Not assigned or no longer used
  • 457 Italian language variations
  • 458 Standard Italian usage
  • 459 Romanian & Rhaeto-Romanic
• 460 Spanish & Portuguese languages
• • 461 Spanish writing system & phonology
  • 462 Spanish etymology
  • 463 Spanish dictionaries
  • 464 Not assigned or no longer used
  • 465 Spanish grammar
  • 466 Not assigned or no longer used
  • 467 Spanish language variations
  • 468 Standard Spanish usage
  • 469 Portuguese
• 470 Italic languages; Latin
• • 471 Classical Latin writing & phonology
  • 472 Classical Latin etymology & phonology
  • 473 Classical Latin dictionaries
  • 474 Not assigned or no longer used
  • 475 Classical Latin grammar
  • 476 Not assigned or no longer used
  • 477 Old, Postclassical, Vulgar Latin
  • 478 Classical Latin usage
  • 479 Other Italic languages
• 480 Hellenic languages; Classical Greek
• • 481 Classical Greek writing & phonology
  • 482 Classical Greek etymology
  • 483 Classical Greek dictionaries
  • 484 Not assigned or no longer used
  • 485 Classical Greek grammar
  • 486 Not assigned or no longer used
  • 487 Preclassical & postclassical Greek
  • 488 Classical Greek usage
  • 489 Other Hellenic languages
• 490 Other languages
• • 491 East Indo-European & Celtic languages
  • 492 Afro-Asiatic languages; Semitic
  • 493 Non-Semitic Afro-Asiatic languages
  • 494 Ural-Altaic, Paleosiberian, Dravidian
  • 495 Languages of East & Southeast Asia
  • 496 African languages
  • 497 North American native languages
  • 498 South American native languages
  • 499 Miscellaneous languages