Muhammad says he spent his youth farming and fighting in the mountains, and never set foot in his town's tiny elementary school.

穆哈马德说他的童年是在农场做活和山里打架中度过的，从来没有进过他镇上那个袖珍小学。

Perhaps one of the most important additions in MathML3 is a new set of functionality for laying out elementary math. These are the tabular layouts used for long multiplication and long division.

也许MathML3中最重要的增加是一组用于布局基本数学公式的新功能，即用于长乘和长除的表格布局。

The difficulties stem from the fact that the interaction between elementary particles and fields is really too violent for a satisfactory theory to be set up.

这些困难来源于这样一个事实：基本粒子和场之间的相互作用对于要建立一个符合要求的理论来说显得过于强烈了。