In the fragments of the text: “they may lose the desire to master whatever task you are asking them to do” (lines 12-13) and “then you have to do more than just present lessons in the app” (lines 18-19), the verb forms in bold express the ideas, respectively, of 
In the sentence of the text: “However, if you want people to continue using the app, and use it frequently and often, then you have to do more than just present lessons in the app” (lines 17-19), the connector However can be replaced, without any change in meaning, by 
Regarding the language underlined in the text, it can be said that 
A palavra que preenche, no contexto, a lacuna A é
In the sentence “There are some real bargains, especially at the top of the market”, the idea brought by the expression in bold is: 
The word disgruntled, as it appears in the text, could be replaced by any of the options below, without changing the meaning, except by: 
No quarto parágrafo, as palavras que correta e respectivamente preenchem os espaços I e II são
Pode-se concluir, a partir da leitura do 2º parágrafo, que o diretor executivo da Microsoft
De acordo com as informações contidas no texto,
Segundo o texto,
