Testing tensor indices <mmultiscripts>: {}_k{}^{3}R_i^1{}_j{}^2; This with <none/>, {}_{i}A_q^p; A bit of calculus with poor markup: ${\int }_a^{b}f\left(x\right)\mathrm{dx}\frac{\partial }{\partial x}F(x,y)+\frac{\partial }{\partial y}F(x,y)$; Here is the alphabet with invisible portions wrapped by <mphantom> in between: a b c \phantom{defghij} k l m n o \phantom{pqrs} t u v w x y z. Testing MathML <msub>: a_b; a_i; A_{I_k}; Testing MathML <msup>: d^b 2^{a_x} {2^2}^x {\left(\frac{1}{2}\right)}^{y^{a_x}}. Testing MathML <munder>, <mover>, and <munderover>: \underset{\mathrm{un}}{\mathrm{abcd}} \stackrel{\mathrm{ov}}{\mathrm{abcd}} \underset{\mathrm{under}}{\overset{\mathrm{over}}{\mathrm{abcd}}}. Testing MathML <msubsup>: a_p^q a_{\mathrm{b+c}}^x. Testing MathML <mrow>: d^{\left(\frac{a}{b}\right)}; x^2+4*x+\frac{p}{q}=0, with this <mfrac> hanging here \frac{d*T^{\left(\frac{\mathrm{i\; +\; j}}{n}\right)}+p_y*q}{p^x*b_x+\frac{a+c}{d}} in the middle of a lot of running text to try to explain what this means to those who care to read. Testing MathML merror, mtext, \text{This is a text in mtext} This\; is\; a\; text\; in\; merror