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SI : Metric system
The International System of Units, abbreviated SI (for the French phrase Système International d'Unités), is the most widely used system of units. Along with the older cgs (centimetre, gram, second) system, SI is sometimes referred to as the metric system (especially in the United States, which has not widely adopted its use in everyday commerce, and the UK where conversion is incomplete). SI is built on seven SI base units, such as the kilogram and metre. These are used to define various SI derived units. SI also defines a number of SI prefixes to be used with the units: these combine with any unit name to give subdivisions and multiples. For example, the prefix kilo denotes a multiple of a thousand, so the kilometre is 1,000 metres, the kilogram 1,000 grams and so on.
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The system can legally be used in every country in the world, and in many countries its use is obligatory. Those countries that still give official recognition to non-SI units (e.g. US, UK) define them in terms of SI units. It was adopted by the 11th General Conference on Weights and Measures (CGPM) in 1960. (See weights and measures for a history of the development of units of measurement).
Americans frequently spell 'metre' as 'meter', and 'litre' as 'liter'; however 'metre' and 'litre' are the official BIPM names for these units, although the American usage has been approved by the US government. The official US spelling for 'deca' is 'deka', though Americans use the international spelling more often than the American one.
The unit 'gram' is also sometimes spelled 'gramme' in English speaking countries, though that is an older spelling. Several other languages use the American spelling. In written practice only the abbreviated (prefixed) symbols are used, qualifying the spelling issue.
The English language version of the official SI brochure (http://www.bipm.org/pdf/si-brochure.pdf) published by the BIPM uses the decimal point instead of the comma to separate the integer portion of a number from the fractional portion. This indicates that the use of the comma isn't an inherent part of SI, but a part of the language and culture in which it is used in a particular case. In the U.S., the decimal point should be used.
Ils ne/ne.html">ne
ces bouquets, on apercevait la ligne des montagnes, qui se/se.html">se dessinaient
du soir.
Le torrent du Nyad, que le forestier n'avait cessé de côtoyer
de distance. A quelques centaines de pieds au/au.html">au/au.html">au-dessus des derniers plis
constructions du burg.
Nic Deck atteignit enfin ce plateau, après un dernier coup de collier
n'aurait pas eu la force de se traîner vingt pas de plus, et il tomba
Debout, immobile, il dévorait du regard ce château des Carpathes, dont
foss.html">fossé profond, et dont l'unique pont-levis.html">levis était redressé contre une
abandon et silence.
Un reste de jour permettait d'embrasser l'ensemble. du burg qui
montrait au-dessus du parapet de la courtine, personne sur la
premier étage. Pas un filet de fumée ne s'enroulait autour de
est.html">est impossible de franchir ce fossé, de baisser ce pont-levis, d'ouvrir
de faire halte devant les murs du château. Au milieu de cette
le long de l'escarpe pour pénétrer dans l'enceinte ? Évidemment, le
lumière.
C'est ce qui fut résolu au grand ennui du forestier, mais à l'extrême
disparu presque aussitôt après le coucher du soleil. Des nuages, venus
crépuscule. L'ombre envahit peu à peu l'espace en montant des basses
burg disparurent bientôt sous la crêpe de la nuit.html">nuit.
Si cette nuit-là menaçait d'être très obscure, rien n'indiquait qu'elle
tempête. C'était heureux pour Nic Deck et son compagnon, qui allaient
et là seulement des buissons ras à ras de terre, qui n'offraient aucun
les unes à demi enfouies dans le sol, les autres, à peine en.
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