How to say serious mistake in different languages

You can say serious mistake as grave erreur in the following countries: Benin; Burkina Faso; Burundi; Central African Republic; Chad; Democratic Republic of the Congo; Djibouti; France; French Guiana; French Polynesia; French Southern Territories; Gabon; Guadeloupe; Guinea; Ivory Coast; Madagascar; Mali; Martinique; Mayotte; Monaco; Niger; Republic of the Congo; Reunion; Saint Barthelemy; Saint Martin; Saint Pierre and Miquelon; Senegal; Togo;

You can say serious mistake as grave error in the following countries: Argentina; Bolivia; Chile; Colombia; Costa Rica; Cuba; Dominican Republic; Ecuador; El Salvador; Equatorial Guinea; Guatemala; Honduras; Mexico; Nicaragua; Panama; Paraguay; Peru; Spain; Uruguay; Venezuela;

You can say serious mistake as ernstige fout in the following countries: Aruba; Belgium; Curacao; Netherlands; Netherlands Antilles; Sint Maarten; Suriname;

You can say serious mistake as erro grave in the following countries: Angola; Brazil; Cabo Verde; Guinea-Bissau; Mozambique; Portugal; Sao Tome and Principe;

You can say serious mistake as 严重错误 in the following countries: China; Hong Kong; Macao; Taiwan;

You can say serious mistake as schwerer fehler in the following countries: Austria; Germany; Liechtenstein; Switzerland;

You can say serious mistake as vakava virhe in the following countries: Finland; Northern Mariana Islands;

You can say serious mistake as σοβαρό λάθος in the following countries: Cyprus; Greece;

You can say serious mistake as grave errore in the following countries: Italy; San Marino;

You can say serious mistake as alvorlig feil in the following countries: Norway; Svalbard and Jan Mayen;

You can say serious mistake as allvarligt misstag in the following countries: Aland Islands; Sweden;

You can say serious mistake as сур'ёзная памылка in the following countries: Belarus;

You can say serious mistake as сериозна грешка in the following countries: Bulgaria;

You can say serious mistake as vážná chyba in the following countries: Czechia;

You can say serious mistake as alvorlig fejltagelse in the following countries: Denmark;

You can say serious mistake as tõsine viga in the following countries: Estonia;

You can say serious mistake as súlyos hiba in the following countries: Hungary;

You can say serious mistake as nopietna kļūda in the following countries: Latvia;

You can say serious mistake as rimta klaida in the following countries: Lithuania;

You can say serious mistake as poważny błąd in the following countries: Poland;

You can say serious mistake as серьезная ошибка in the following countries: Russia;

You can say serious mistake as vážna chyba in the following countries: Slovakia;

You can say serious mistake as ciddi hata in the following countries: Turkey;

You can say serious mistake as серйозна помилка in the following countries: Ukraine;