The word "<u><em>visitando</em></u>" is the one that gives more meaning to the sentence, it is used when you say that a person is exploring places and looking at the culture, the continuous verb is used (because the action is happening at that moment) "visit "conjugating it with the pronoun in the sentence.
So, the sentence in Spanish is:
<em>Sophie y Charlie están </em><em><u>visitando</u></em><em> muchos lugares en Honduras y El Salvador.</em>
Para deshacerse del petróleo, debe empobrecer el aceite en una caja de cartón y ponerlo en la basura. No hacer esto puede matar las plantas<span> </span>
