DJ音标发音： [ˈtu:baiˌfɔ:r, -ˌfour, ˈtu:bə-]
KK音标发音： [ˈtubaɪˌfɔr, -ˌfor, ˈtubə-]
1. Measuring two units by four units, especially inches.
2. Slang Small in size; boxed in or cramped:
a two-by-four apartment.
3. A length of lumber that is 2 inches thick and 4 inches wide, or that is trimmed to slightly smaller dimensions.