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diff --git a/english/ex/theme-13-reading-rules/teoria-from-zero.md b/english/ex/theme-13-reading-rules/teoria-from-zero.md
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@@ -29,7 +29,7 @@
| a | [æ] | `cat` [kæt], `map` [mæp] | |
| e | [e] | `bed` [bed], `pen` [pen] | |
| i | [ɪ] | `sit` [sɪt], `big` [bɪɡ] | |
-| o | [ɒ] (брит.) / [ɑ] (амер.) | `hot` [hɒt] / [hɑt], `dog` [dɒɡ] / [dɑɡ] | |
+| o | [ɑ] | `hot` [hɑt], `box` [bɑks] | |
| u | [ʌ] | `cup` [kʌp], `sun` [sʌn] | |
| y | [ɪ] | `gym` [dʒɪm], `system` [ˈsɪstəm] | |