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Complete the following exercises
about logical sentences:<br />

1.  Translate into *good, natural* English (no $x$s or $y$s!):<br />

$$
{\forall\,x,y,l\;\;} SpeaksLanguage(x, l) \land SpeaksLanguage(y, l)
    \implies Understands(x, y) \land Understands(y,x).<br />
$$

2.  Explain why this sentence is entailed by the sentence<br />

$$
{\forall\,x,y,l\;\;} Sp